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Recent problems solved by 'rfer'

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expressions/375646: Simplify. Please show all of your work. 2-3^3/27-7+30 1 solutions Answer 267121 by rfer(12730)   on 2010-11-23 20:24:44 (Show Source): You can put this solution on YOUR website! 2-27/27-7+30=24

expressions/375644: Evaluate and, if possible, simplify. -6-x/12 for x = -6 1 solutions Answer 267119 by rfer(12730)   on 2010-11-23 20:22:23 (Show Source): You can put this solution on YOUR website! -6--6/12 -6+.5=-5.5 ---------- -72/12+6/12=-66/12=-5 1/2

Linear-equations/375550: what is the slope of 3/4 1 solutions Answer 267084 by rfer(12730)   on 2010-11-23 17:55:01 (Show Source): You can put this solution on YOUR website! rise over run on the grapg from a starting point go 4 right and 3 up for a positive slope

Travel_Word_Problems/375584: If two runners start at the same time from opposite ends of a course that is 20 miles long, one goes at 8mph and one goes at 12mph, how long after they begin will they meet? 1 solutions Answer 267081 by rfer(12730)   on 2010-11-23 17:52:32 (Show Source): You can put this solution on YOUR website! 1 hr

Equations/375579: an apartment contains 12 units consisting of one and two bedroom apartments that rent for $360 and $450 per month, respectively. when all units are rented, the total monthly rental is $4,950. what is the number of two bedroom apartments? 1 solutions Answer 267080 by rfer(12730)   on 2010-11-23 17:49:33 (Show Source): You can put this solution on YOUR website! 360x+450(12-x)=4950 360x+5400-450x=4950 -90x=-450 x=5 one bed 450-x=7 two bed

Travel_Word_Problems/375562: A cyclist travels 15 mph, find the rate at ft. per minute? 1 solutions Answer 267077 by rfer(12730)   on 2010-11-23 17:40:48 (Show Source): You can put this solution on YOUR website! 15/60=0.25 mpm 5280*0.25=1320 ft/m

Expressions-with-variables/375432: solve the system 3x-y=8 and x+2y=5 1 solutions Answer 267055 by rfer(12730)   on 2010-11-23 15:44:48 (Show Source): You can put this solution on YOUR website! x=-2y+5 3(-2y+5)-y=8 -6y+15-y=8 -7y=-7 y=+1 ----------------- x+2*1=5 x=3 --------------- 3*3-1=8

Distributive-associative-commutative-properties/375427: Simplify x(4x2 + 3x-5)-2(4-x2) Find the Product (b+2)(b+6) Find the Product (7x+1)(x2+1) Find the Product (2x+6)(x-10) Evaluate (a+b)2 1 solutions Answer 267054 by rfer(12730)   on 2010-11-23 15:40:50 (Show Source): You can put this solution on YOUR website! 4x^3+3x^2-5x-8+2x^2 4x^3+5x^2-5x-8 ---------------- (b+2)(b+6) b^2+6b+2b+12 b^2+8b+12 ---------------- (a+b)(a+b) a^2+ab+ab+b^2 a^2+2ab+b^2

Money_Word_Problems/375448: What is the simple interst on $1800 at 6% for 1/3 year? 1 solutions Answer 267052 by rfer(12730)   on 2010-11-23 15:34:50 (Show Source): You can put this solution on YOUR website! I=1800*.06*1/3 I=108/3 I=$36

Miscellaneous_Word_Problems/375480: By 3:00 PM, Erin had plowed 7 driveways and by 5:30 PM she had completed 13. a) Find Erin’s plowing rate in number of driveways per hour. b) Find Erin’s plowing rate in minutes per driveway 1 solutions Answer 267051 by rfer(12730)   on 2010-11-23 15:32:16 (Show Source): You can put this solution on YOUR website! 6/2.5=2.4 per hr

Polynomials-and-rational-expressions/375512: how to solve 67=-3y+16 1 solutions Answer 267050 by rfer(12730)   on 2010-11-23 15:30:22 (Show Source): You can put this solution on YOUR website! 3y=-51 y=-17

Equations/375450: 7x-1= 5x 1 solutions Answer 267048 by rfer(12730)   on 2010-11-23 15:29:13 (Show Source): You can put this solution on YOUR website! 2x=1 x=1/2

Graphs/375479: 31 more than half another number equals 70. What are the two numbers? 1 solutions Answer 267045 by rfer(12730)   on 2010-11-23 15:26:53 (Show Source): You can put this solution on YOUR website! .5x+31+x=70 1.5x=39 x=26 .5x+31=44

Geometry_Word_Problems/375213: These are the data: 6,6,6,5,5,6,5,6,5. Find the mean, median, mode, and range of the data. If necessary, round to the nearest tenth. 1 solutions Answer 266851 by rfer(12730)   on 2010-11-22 23:02:51 (Show Source): You can put this solution on YOUR website! mean=5.6 median=6 mode=6 range=1

Numbers_Word_Problems/375238: 3/8 x- -1 = 4 1 solutions Answer 266850 by rfer(12730)   on 2010-11-22 22:59:01 (Show Source): You can put this solution on YOUR website! x=3*8/3 x=8

Problems-with-consecutive-odd-even-integers/375253: The product of two consecutive integers x and y is 156. Find the two integers. (Assume x < y.) 1 solutions Answer 266849 by rfer(12730)   on 2010-11-22 22:57:31 (Show Source): You can put this solution on YOUR website! 12*13=156

Angles/375215: find the supplementary angle of 126.8 degrees 1 solutions Answer 266834 by rfer(12730)   on 2010-11-22 21:54:53 (Show Source): You can put this solution on YOUR website! 180-126.8=53.2

test/375126: A bus company charges a flat rate of $200.00 for a one day bus trip plus $25.00 for each person let x be the number of people taking the trip and f(x) be the total cost Write an equation for the cost of the bus trip for x people 1 solutions Answer 266807 by rfer(12730)   on 2010-11-22 20:22:07 (Show Source): You can put this solution on YOUR website! f(x)=200+25x

Evaluation_Word_Problems/375181: you split 1500 between two savings accounts. account A pays 5% intrest and account B pays 4% annual intrest. after one year you have earned a total of 69.50 in intrest. what would be the two equations? 1 solutions Answer 266805 by rfer(12730)   on 2010-11-22 20:17:34 (Show Source): You can put this solution on YOUR website! .05x+.04(1500-x)=69.50 .05x+60-.04x=69.50 .01x=9.50 x=950 at 5% 1500-x=550 at 4%

Money_Word_Problems/375130: tracy has 4,300 in his savings account. The money in the account earns 4.6% interest each year. Assuming he makes no more deposits, how much money will tracy have in his account at the end of one year? 1 solutions Answer 266802 by rfer(12730)   on 2010-11-22 20:10:10 (Show Source): You can put this solution on YOUR website! A=4300*1.046=4,497.80

Numeric_Fractions/374720: The interest rate on a mortgage was 7 3/4 % last year. This year the interest rate is 9 1/4 %. How many percentage points has the interest rate increased? 1 solutions Answer 266532 by rfer(12730)   on 2010-11-22 00:50:54 (Show Source): You can put this solution on YOUR website! 1.5

Money_Word_Problems/374744: Mark and Kate are establishing a fund for their son's college education. What lump sum must they deposit in an account that gives 6% annual interest rate, compounded monthly, in order for them to have $65,000 in the fund at the end of 10 years? 1 solutions Answer 266531 by rfer(12730)   on 2010-11-22 00:48:55 (Show Source): You can put this solution on YOUR website! 65000=P(1+0.06/12)^(12*10) P=65000/(1.005)^120 P=65000/1.819396734 P=35,726.13

Travel_Word_Problems/374756: Two trains leave the station at the same time, one heading east and the other west. The eastbound train travels at 75 miles per hour. The westbound train travels at 95miles per hour. How long will it take for the two trains to be 238 miles apart? 1 solutions Answer 266530 by rfer(12730)   on 2010-11-22 00:44:11 (Show Source): You can put this solution on YOUR website! moving apart at 75+95=170 mph 238/170=1.4 hrs=1 hr 24 min

Travel_Word_Problems/374727: what is the average speed of miles per hour if distance is 200 miles with 4 1/6 hours 1 solutions Answer 266529 by rfer(12730)   on 2010-11-22 00:42:12 (Show Source): You can put this solution on YOUR website!

Travel_Word_Problems/374729: what is the average speed of miles per hour if distance is 200 miles with 4 1/6 hours 1 solutions Answer 266528 by rfer(12730)   on 2010-11-22 00:41:36 (Show Source): You can put this solution on YOUR website! 200*6/25=1200/25=48 mph

Percentage-and-ratio-word-problems/374748: if you go on a motorcycle ride of 90 miles in the mountains and 3.5ths of it is downhill..how many miles are not downhill? 1 solutions Answer 266527 by rfer(12730)   on 2010-11-22 00:38:06 (Show Source): You can put this solution on YOUR website! 90*2/5=180/5=36 miles

Miscellaneous_Word_Problems/374771: At 6h00 a clock strikes the bell 6 times. The time between first and last strike is 30 seconds. How long does it take to strike the bell at 12h00 ? 1 solutions Answer 266526 by rfer(12730)   on 2010-11-22 00:34:39 (Show Source): You can put this solution on YOUR website! 60 sec

Numeric_Fractions/374766: simplify each expression 3/4 divided by 6/5+8/12 times 6/9 -5/12 1 solutions Answer 266525 by rfer(12730)   on 2010-11-22 00:33:02 (Show Source): You can put this solution on YOUR website! 3/4*5/6+8/12*6/9-5/12 15/24+48/108-5/12 5/8+4/9-5/12 45/72+32/72-30/72=47/72

Numeric_Fractions/374777: reduce to the lowest term.. (-6/7)divided by (5/7)(-5/6) 1 solutions Answer 266523 by rfer(12730)   on 2010-11-22 00:27:07 (Show Source): You can put this solution on YOUR website! -6/7*7/5*-5/6=210/210=1

Average/374696: What is the slope of the line described by -6x = -2y + 5? 1 solutions Answer 266482 by rfer(12730)   on 2010-11-21 21:08:31 (Show Source): You can put this solution on YOUR website! 2y=6x+5 y=3x+2.5 slope m=3

Percentage-and-ratio-word-problems/374681: how do you solve this? --> a jacket costs $120 which includes a 5% sales tax. what was the cost of the jacket without the tax? 1 solutions Answer 266481 by rfer(12730)   on 2010-11-21 21:07:00 (Show Source): You can put this solution on YOUR website! 120/1.05=114.29