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Volume/343372: There are three separate tunnels built side. Each is 50,000 meters long and 4ft. high. How many cubic meters of dirt had to be moved using 3.14 pi? 1 solutions Answer 245711 by mananth(12270)   on 2010-09-15 09:27:08 (Show Source): You can put this solution on YOUR website! 1 ft. = 0.3048 m 4ft = 4*0.3048=1.22m we assume it is a cylinder of 50000m with diameter 1.22m radius = 0.61m volume V = pi*r^2 * h V= 3.14 *0.61*0.61*50000 V = 58419.7 cu.m of dirt was removed this is for 1 tunnel you calculate for 3 tunnels.

test/343382: Factor completely 6x^7-36x^6+18x^5 please put factor form 1 solutions Answer 245709 by mananth(12270)   on 2010-09-15 09:19:02 (Show Source): You can put this solution on YOUR website! 6x^7-36x^6+18x^5 .. 6x^5(x^2-6x+3)

Linear_Equations_And_Systems_Word_Problems/343381: The product of twenty less than eight times a number and thirty less than two times a number equals zero. Find the number(s). 1 solutions Answer 245707 by mananth(12270)   on 2010-09-15 09:13:22 (Show Source): You can put this solution on YOUR website! (8x-20)(2x-30)=0 16x^2-240x-40x+600=0 16x^2-280x +600 =0 divide by 8 2x^2-35x+75=0 2x^2-30x-5x+75=0 2x(x-15)-5(x-15)=0 (x-15)(2x-5)=0 x=15 OR 5/2

Geometry_Word_Problems/343338: the second angle of a triangular kite is four times as large as the first. The third angle is 5 degrees more than the sum of the other two angles. Find the measure of the second angle. 1 solutions Answer 245686 by mananth(12270)   on 2010-09-15 05:35:41 (Show Source): You can put this solution on YOUR website! let first angle be x the second angle = 4x .. Third angle =(x+4x)+5 .... x+4x+5x+5 =180 10x+5 =180 -5 10x+5-5 = 180-5 10x = 175 /10 x= 175/10 x =17.5 first angle second angle = 4x = 4*17.5 = 70 deg third angle = 5x+5 = 5*17.5 + 5= 92.5 deg

Systems-of-equations/343350: 6h - 7 = 17 Can you answer and show steps? 1 solutions Answer 245685 by mananth(12270)   on 2010-09-15 05:27:46 (Show Source): You can put this solution on YOUR website! 6h-7=17 add +7 on both sides 6h-7+7 = 17+7 6h=24 divide by 6 on both sides 6h/h = 24/6 h=4

Money_Word_Problems/343329: A pound of tin is worth $1 more than a pound of copper. Two pounds of tin are mixed with 8 pounds of copper to make bronze that sells for $3.30 per pound. How much is a pound of tin worth? 1 solutions Answer 245682 by mananth(12270)   on 2010-09-15 03:05:06 (Show Source): You can put this solution on YOUR website! A pound of tin is worth $1 more than a pound of copper. Two pounds of tin are mixed with 8 pounds of copper to make bronze that sells for $3.30 per pound. How much is a pound of tin worth? let 1 pound of copper cost $ x Tin will be x+1 .. 2(x+1)+8x = 10*3.30 2x+2+8x =33 10x+2=33 -2 10x= 33-2 10x=31 /10 x= 3.1

Money_Word_Problems/343332: A professor wants to supplement her pension with investment interest. If she invests $31,000 at 6% interest, how much more would she have to invest at 7% to achieve a goal of $2,560 per year in supplemental income? 1 solutions Answer 245681 by mananth(12270)   on 2010-09-15 02:57:48 (Show Source): You can put this solution on YOUR website! 31000 at 6% so interest = 0.06 * 31000 =$1860 Total interest to be earned = $2560 Balance to be earned = $2560-$1860 =$700 .. I= p*r*t 700=p*0.07*1 700/0.07 =p p= $10,000 This is the investment required.

Miscellaneous_Word_Problems/343335: It takes a girl 36 minutes to deliver the newspapers on her route; however, if her brother helps, it takes them only 20 minutes. How long would it take her brother to deliver the newspapers by himself? 1 solutions Answer 245680 by mananth(12270)   on 2010-09-15 02:47:44 (Show Source): You can put this solution on YOUR website! girl takes 36 minutes 1/36 of the job she does in 1 minute .. together they do do in 20 minutes 1/20 of the job they do in 1 minute .. 1/20 -1/36 = (36-20) / 20*36 =16/20*36 =1/45 of the job he does alone so he will take 45 minutes to do the job alone.

Angles/343341: if two angles are supplementary and the larger angle is 20 degrees less then three times the the smaller angle find the measure of each angle 1 solutions Answer 245675 by mananth(12270)   on 2010-09-15 02:40:49 (Show Source): You can put this solution on YOUR website! let smaller angle be x the supplement will be 180-x .. 180-x =3x-20 3x+x=180+20 4x =200 /4 x= 50 deg. the other angle = 180-x =180-50 = 130 deg.

Graphs/343348: HOW DO I WRITE AN INEQUALITY FOR A GRAPH USING -2X-3Y=6 1 solutions Answer 245672 by mananth(12270)   on 2010-09-15 02:36:34 (Show Source): You can put this solution on YOUR website! -2X-3Y=6 this is not an inequality .. add +2x to both sides -2x+2x-3y=6+2x -3y=2x+6 divide by -3 y= (-2/3) x +2

Geometry_Word_Problems/343342: One side of a triangle is half the longest side. The third side is 10 meters less than the longest side. The peremiter is 53 feet. Find the shortest side. 1 solutions Answer 245666 by mananth(12270)   on 2010-09-15 02:14:18 (Show Source): You can put this solution on YOUR website! let longest side = x one side = x/2 third side =x-10 ... x+x/2 + x-10=53 +10 2x+x/2 +10-10=53+10 2x+x/2 = 63 (4x+x)/2 =63 LCD =2 5x/2 = 63 multiply by 2 5x= 2*63 /5 x= 2*63/5 =25.2 .. x/2 = 25.2 /2 = 12.6 x-10 = 25.2 -10=15.2 The sides are 25.2 , 12.6, 15.2 Check Their sum = 53

Geometry_Word_Problems/343343: Barbara had money in two accounts. She had $900 more in an account paying 8% annual interest than she had in an account paying 6% annual interest. If she earned $240 in interest for the year, how much did she have invested in each account? 1 solutions Answer 245664 by mananth(12270)   on 2010-09-15 02:04:45 (Show Source): You can put this solution on YOUR website! 6% account be $ x 8% account she has x+900 .. Total interest she earned =$240 .. 0.06x+0.08(x+900)=240 0.06x +0.08x + 72=240 0.14x= 240-72 0.14x= 168 /0.14 x= 168/0.14 =$1200 amount at 6 % 1200+900 = $2100 at 8%

Travel_Word_Problems/343345: A bus traveling at an average rate of 50 kilometers per hour made the trip to town in 6 hours. If it had traveled at 45 kilometers per hour, how many more minutes would it have taken to make the trip? 1 solutions Answer 245663 by mananth(12270)   on 2010-09-15 01:59:07 (Show Source): You can put this solution on YOUR website! Distance = speed * time =50*6=300 km ... Time = distance / speed Time = 300 /45 time = 6.66 hours .. It takes 0.66 hours more = 0.66 *60 = 39.6 minutes = 40 minutes

Geometry_Word_Problems/343320: A swimming pool is 16 feet wide and 40 feet long. If it is surrounded by square tiles, each of which is 1 foot by 1 foot, how many tiles are there surrounding the pool? 1 solutions Answer 245646 by mananth(12270)   on 2010-09-14 23:34:27 (Show Source): You can put this solution on YOUR website! Firstly, we have to find the area of the tiles laid. .. Area of tiles laid = Total area ( including tiles ) - the area of the pool. .. Area of pool = 16 * 40 = 640 sq.ft. .. The tile is 1 foot in length and width. add 2 to length & width of pool the width = 16+2 = 18 the length = 40 +2 = 42 Total Area including tile Area = 18*42= 756 sq. ft ... Area of tiles = 756-640=116 sq.ft. .. one tile is 1*1 = 1 sq. ft. area = 116 sq.ft Number of tiles = 116.

Quadratic_Equations/343315: how do I figure this problem out -3/x = x/-3 1 solutions Answer 245642 by mananth(12270)   on 2010-09-14 23:27:26 (Show Source): You can put this solution on YOUR website! -3/x = x/-3 multiply by -x -3/x *-x= x*-x/-3 3= x^2/3 multiply by 3 3*3=x^2/3 * 3 9=x^2 take square root x= =/- 3

test/343311: As we are learning rational expressions a classroom mate is asking everyone to solve his problem. How would I solve this, √32^5+ √23^6*(14-9) 1 solutions Answer 245640 by mananth(12270)   on 2010-09-14 23:23:26 (Show Source): You can put this solution on YOUR website! I am not too sure about the way the problem is written.

Travel_Word_Problems/343254: I do not know how to go about solving this problem. "You drive to the city at an average speed of 40km/h and return at an average speed of 60km/h. Find your average speed for the entire trip? Explain why the answer is not 50km/h" when i read the problem i assumed the answer was 50km/h because that was the average between the two. But after i read the last sentence, it changed my view on how to solve the problem. I need help on the process to answer the problem. 1 solutions Answer 245603 by mananth(12270)   on 2010-09-14 21:22:47 (Show Source): You can put this solution on YOUR website! .. you will see that speed is a function of time and distance. speed varies with time, distance being same. .. In the problem the distance is same but the time taken is different. .. If the city was 120 miles .. time going will be 120/40 = 3hours time returning = 120/60 = 2hours Total 5 hours. .. Distance is 240 time = 5 speed = 240/5 speed = 48 mph is the average speed

Equations/343253: -3+8K-2K=4K+7+4K 1 solutions Answer 245601 by mananth(12270)   on 2010-09-14 21:12:18 (Show Source): You can put this solution on YOUR website! -3+8K-2K=4K+7+4K -3+6K=8K+7 +3 -3+3+6k=8K+7+3 6K=8K+10 -8K 6K-8K=8K-8K+10 -2K=10 /-2 K=-5

Systems-of-equations/343249: Please help me solve this problem: -1/2 - (-5/8) = 1 solutions Answer 245600 by mananth(12270)   on 2010-09-14 21:09:16 (Show Source): You can put this solution on YOUR website! LCD = 8

test/343243: The sum of two consective whole numbers is 57. What are the two numbers? (Hint: Let n represent the first number. Then n +1 is the next consecutive whole number.) 1 solutions Answer 245598 by mananth(12270)   on 2010-09-14 21:05:07 (Show Source): You can put this solution on YOUR website! n + n+1 =57 2n+1=57 -1 2n+1-1=57-1 2n=56 /2 n=56/2 n=28 .. the numbers are 28,29

Numbers_Word_Problems/343233: The sum of three consecutive natural numbers is 15 more than the greatest of them. What is the greatest of the three numbers? 1 solutions Answer 245597 by mananth(12270)   on 2010-09-14 21:02:14 (Show Source): You can put this solution on YOUR website! let the numbers be x,x+1,x+2 ... x+x+1+x+2=15+x+2 3x+3=x+17 -x 3x-x+3=x-x+17 2x+3=17 -3 2x-3+3 = 17-3 2x=14 /2 x= 7 the third number ix 7+2=9

Travel_Word_Problems/343237: an express train leaves grand central station 1 hour after a freight train leaves the same station. the express train is traveling 15 mph faster that the freight treain.find the rate at which each train is traveling if the express train overtakes the freight train in 3 hours. 1 solutions Answer 245594 by mananth(12270)   on 2010-09-14 20:54:58 (Show Source): You can put this solution on YOUR website! freight train speed be x mph express train speed = x+15 mph .. the express train leaves the station 1 hour later. .. express train travels 3(x+15)miles freight train travels 4x miles 4x=3(x+15) 4x=3x+45 4x-3x=45 x=45 mph the speed of freight train. speed of express train = x+15 = 60 mph

Linear-equations/343231: How would you graph the inequality on a plane? 5x-6y<30 1 solutions Answer 245588 by mananth(12270)   on 2010-09-14 20:45:14 (Show Source): You can put this solution on YOUR website! 5x-6y<30 -5x 5x-5x-6y<30-5x -6y<-5x+30 divide by -6 y>(5x/6) -5 ... take various values for x like -1,1,2,3 (6,0) calculate y and plot the graph as if y = something Since y> something all values above the line are solutions. Since y> the line should be a dotted one.

Linear-systems/343219: my problem is in any triangle the sum of the measures of the angles is 180 degrees. In triangle ABC, angle A is four times as large as angle B. Angle C measures 20 degrees less than angle B. Find the measure of each angle. we are suposed to turn it into an equation find an angle then solve the problem from there. i cannot think of an equation. i have tried: 180= 4X+X-20 and other equations but none work thank you for helping me! 1 solutions Answer 245584 by mananth(12270)   on 2010-09-14 20:33:49 (Show Source): You can put this solution on YOUR website! let angle B be x Angle A = 4x Angle C = x-20 .. x+4x+x-20 =180 6x-20=180 +20 6x=180+20 6x=200 x= 33.33 Angle B .. Angle A = 4x = 133.32 Angle C =x-20= 13.33 CHECK 33.33 + 133.32 + 13.33

Triangles/342840: One side of a triangle is three times the shortest side. The third side is 7 feet more than the shortest side. The perimeter is 62 feet. Find all three sides. 1 solutions Answer 245356 by mananth(12270)   on 2010-09-14 06:56:33 (Show Source): You can put this solution on YOUR website! shortest side be x one side = 3x third side= x+7 ... x+x+7+3x=62 5x+7=62 -7 5x+7-7=62-7 5x=55 /5 x= 55/5 x=11 3x = 33 11+7=18 .. 11, 33, 18

Triangles/342841: The lenght of a rectangle is 5 inches more than the width. The perimeter is 34 inches. Find the lenght and the width? 1 solutions Answer 245355 by mananth(12270)   on 2010-09-14 06:51:15 (Show Source): You can put this solution on YOUR website! width be x length = x+5 .. Perimeter P = 2*(L+W) 2(x+x+5)=34 4x+10=34 divide by 2 2x+5=17 -5 2x= 17-5 2x=12 x=6in length = x+5= 6+5 =11 in

Numeric_Fractions/342824: Hi. I recently studied fractions involving binomials and polynomials as common denominators, and right now I'm studying problems of adding and subtracting fractions with different denominators. I really have a problem involving this problem: 3 - 7x over 8x^2 -18 + 3 + x - 4 - x over 2x^2 - 9x + 9 Can you please tell me how exactly do I figure out what LCD to multiply with the numerator, and what to do with the expressions in the middle that aren't fractions? (the 3 and the x) Thank you very much. 1 solutions Answer 245352 by mananth(12270)   on 2010-09-14 04:49:41 (Show Source): You can put this solution on YOUR website! lease write the problem so that we understand. put brackets to make it clear. we will respond. or write to me

Evaluation_Word_Problems/342820: Robert has 39 coins in his pocket. They are all dimes and quarters and total $6.00. How many of each does he have? 1 solutions Answer 245351 by mananth(12270)   on 2010-09-14 04:45:04 (Show Source): You can put this solution on YOUR website! let dimes be x quarters will be 39-x value 600 cents .. 10x+25(39-x)=600 10x+975-25x=600 -15x=600-975 -15x=-375 x=-375/-15 x=25 dimes 14 will be quarters. CHECK 25*14 +25*10= 600

Numbers_Word_Problems/342793: zarina spent one fourth of her money on food, three tenths of her money on books, and two fifths of her money on records.if she spent $95 on these three items all together, how much money did she have to begin wity? 1 solutions Answer 245335 by mananth(12270)   on 2010-09-13 23:58:55 (Show Source): You can put this solution on YOUR website! zarina spent one fourth of her money on food, three tenths of her money on books, and two fifths of her money on records.if she spent $95 on these three .. let the money she has be $x x/4 + 3x/10 + 2x/5 = 95 LCD= 20 (5x+6x+8x)/20 = 95 19x= 20*95 19x=1900 x =1900/19 x = $100 the cash she had initially

Volume/342781: a reservoir measures 180 ft. in diameter and 20 ft. high. How many gallons of water per foot are in this reservoir? A) 190,246 B)648,000 C) 242,352 D) 508, 680 I thought i used this equation (.785)(180ft)^2(20)(7.48 gals) but it never comes close to one of the answers please help if you can it is for my water distrabution class 1 solutions Answer 245333 by mananth(12270)   on 2010-09-13 23:54:40 (Show Source): You can put this solution on YOUR website! The question is water per foot? diameter = 180 feet radius = 90 feet height of water = 1 foot. Volume V = pi*r^2*h V= pi*90^2*1 V= 508938 cu.ft. .. 1 cu.ft = 7.48 gallons 508,938 cu.ft = 7.48*508938=190,342 gallons

Rate-of-work-word-problems/342784: Please help me with this question! It takes you 9 mins to wash a car and it takes your friend 12 mins to wash a car. How long does it take the two of you to wash 7 cars if you work together? 1 solutions Answer 245332 by mananth(12270)   on 2010-09-13 23:42:05 (Show Source): You can put this solution on YOUR website! I take 9 minutes so 1/9 of the job I do in 1 minute .. my friend takes 12 minutes he tdoes 1/12 of the job in 1 minute .. Together they can do 1/9+1/12 of the job in 1 minute LCD 36 (4+3)/36 7/36 of the job they do in 1 minute so they take 36/7 minutes to clean the car together 5.14 hours 7 cars they take 7*5.14 = 35.98 minutes