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Recent problems solved by 'rfer'

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Exponents/437450: Write each answer in exponential form with only postive exponents 9^2/3 over 9^-1/3 1 solutions Answer 302670 by rfer(12662)   on 2011-04-18 18:59:38 (Show Source): You can put this solution on YOUR website! 1^3/3=1

Average/437455: 6x10^6 divided by 3x10^-3 1 solutions Answer 302665 by rfer(12662)   on 2011-04-18 18:48:52 (Show Source): You can put this solution on YOUR website! 2x10^9 divide the numbers and subtract the exponents 6--3=9

Rectangles/437515: What is the area of the rectangular cage with a side of length 10meters? I do not understand this?!!! 1 solutions Answer 302662 by rfer(12662)   on 2011-04-18 18:45:10 (Show Source): You can put this solution on YOUR website! I am guessing that it is a square with all sides =10 A=10*10 A=100 meters

Geometric_formulas/437448: Given the formula, solve for the indicated variable. A=1/2bh for b 1 solutions Answer 302659 by rfer(12662)   on 2011-04-18 18:41:36 (Show Source): You can put this solution on YOUR website! b=A/(1/2h)

Numbers_Word_Problems/437512: THE product of two 2-digit numbers is 2,000. Their sum is 90. What are the numbers 1 solutions Answer 302656 by rfer(12662)   on 2011-04-18 18:35:47 (Show Source): You can put this solution on YOUR website! 40*50=2000 40+50=90

Rectangles/437509: Is it possible to make a rectangle with an area of 42 square units and a perimeter of 28 units? 1 solutions Answer 302653 by rfer(12662)   on 2011-04-18 18:34:37 (Show Source): You can put this solution on YOUR website! = yes

Average/437506: To get a B in math, Alexandria Papas must average 80 on five test. Scores on the first 4 tests were 83, 74, 83 and 74. What is the lowest score that she can get on the last test and still get a B? 1 solutions Answer 302652 by rfer(12662)   on 2011-04-18 18:30:50 (Show Source): You can put this solution on YOUR website! (83+74+83+74+x)/5=80 314+x=400 x=400-314 x=86

Linear-equations/437460: Find the slope-intercept equation of the line that has the given characteristics. m= -3 (0,8) 1 solutions Answer 302649 by rfer(12662)   on 2011-04-18 18:28:46 (Show Source): You can put this solution on YOUR website! y=mx+b 8=-3*0+b b=8 -------------- y=-3x+8

Volume/437505: I have a round tank that is 3 feet in diameter and 8 feet deep. How many gallons of water will it hold? 1 solutions Answer 302647 by rfer(12662)   on 2011-04-18 18:25:52 (Show Source): You can put this solution on YOUR website! V=3.14r^2h V=3.14*1.5^2*8 V=56.52 cuft --------- 1 cuft=7.5 gal ---------- 56.52*7.5=423.9 gal

Linear-equations/437461: Find an equation of the line having the given slope and containing the given point. m= 8 (7,4) 1 solutions Answer 302645 by rfer(12662)   on 2011-04-18 18:20:37 (Show Source): You can put this solution on YOUR website! y=mx+b 4=8*7+b 4=56+b b=-52 ----------- y=8x-52

Numbers_Word_Problems/437503: find the number that is 16 less than the product of 21 times 15 1 solutions Answer 302644 by rfer(12662)   on 2011-04-18 18:16:30 (Show Source): You can put this solution on YOUR website! (21*15)-16=x 315-16=x x=299

Geometry_Word_Problems/437474: A circular garden has an area of approximately 450 ft^2. Find the radius. Round the answer to the nearest tenth of a foot. 1 solutions Answer 302643 by rfer(12662)   on 2011-04-18 18:13:01 (Show Source): You can put this solution on YOUR website! A=3.14r^2 450/3.14=r^2 r^2=143.3 r=12.0 ft

test/437498: (6c-5)(6c+5) 1 solutions Answer 302641 by rfer(12662)   on 2011-04-18 18:08:56 (Show Source): You can put this solution on YOUR website! 36c^2+30c-30c-25= 36c^2-25

Linear_Algebra/437500: please help me solve this equation 2.6q-4.2-3.9q=-2.3q-2.7 1 solutions Answer 302639 by rfer(12662)   on 2011-04-18 18:07:05 (Show Source): You can put this solution on YOUR website! -1.3q=-2.3q+1.5 q=1.5

Equations/437501: If the base angles of an isosceles triangle are congruent and the measure of the base angle is double the measure of the third angle, then what is the measure of the third angle? 1 solutions Answer 302637 by rfer(12662)   on 2011-04-18 18:04:56 (Show Source): You can put this solution on YOUR website! 180/5=36 degrees

Polynomials-and-rational-expressions/437191: Solve using the addition principle. x – 12 = -30 1 solutions Answer 302516 by rfer(12662)   on 2011-04-18 12:07:41 (Show Source): You can put this solution on YOUR website! x=-18

Age_Word_Problems/437327: If 2 shirts can be bought for $47, how many shirts can be bought with $200? 1 solutions Answer 302514 by rfer(12662)   on 2011-04-18 12:05:49 (Show Source): You can put this solution on YOUR website! 2/47=x/200 47x=400 x=8.5 can't buy 1/2 a shirt so =8

Rectangles/437254: if the long side of a golden rectangle is 39cm, what is the area? 1 solutions Answer 302513 by rfer(12662)   on 2011-04-18 12:03:49 (Show Source): You can put this solution on YOUR website! 1:1.618 39/1.618=24.1 A=24.1*39 A=939.9 sq cm

Expressions-with-variables/437290: if a circuit has a3.9k resistor and a 5uf capacitor, find the current flow in the circuit at 0.005 seconds, if the maximum current flow in the circuit is1.5ma 1 solutions Answer 302511 by rfer(12662)   on 2011-04-18 11:55:02 (Show Source): You can put this solution on YOUR website! the RC time constant is 19.5 Sorry I don't remember the rest

Numeric_Fractions/437090: -56 divid by -7 1 solutions Answer 302378 by rfer(12662)   on 2011-04-17 22:30:44 (Show Source): You can put this solution on YOUR website! -56/-7=+8

percentage/437173: What number is 40% of $236 1 solutions Answer 302377 by rfer(12662)   on 2011-04-17 22:28:43 (Show Source): You can put this solution on YOUR website! 236*0.4=94.4

Miscellaneous_Word_Problems/437085: Pricing. The Book Barn prices its paperbacks by raising the whole sale price 60% and then adding 50 cents. What is the whole sale price of a paper back that sells for $7.95? 1 solutions Answer 302376 by rfer(12662)   on 2011-04-17 22:27:45 (Show Source): You can put this solution on YOUR website! 7.95-.50=7.45 7.45/1.6=4.66

Quadratic_Equations/437162: how to solve the square root of 6 times the square root of 8? 1 solutions Answer 302375 by rfer(12662)   on 2011-04-17 22:22:15 (Show Source): You can put this solution on YOUR website! 6*8=48 sqrt 48=6.93

test/437168: James wishes to enclose a rectangular dog kennel with 150 feet of fencing. He would like the kennel to be twice as long as it is wide. What must be the kennel's dimensions? 1 solutions Answer 302371 by rfer(12662)   on 2011-04-17 22:20:34 (Show Source): You can put this solution on YOUR website! 2w+2(2w)=150 6w=150 w=25 2w=50

Linear_Equations_And_Systems_Word_Problems/436987: What is two more than 4 times a number that is the number less than 7? A. -9/5 B. 1 C. -3 D. -5/6 1 solutions Answer 302307 by rfer(12662)   on 2011-04-17 17:46:11 (Show Source): You can put this solution on YOUR website! 4x+2=7-x 5x=5 x=1 B) 1

Percentage-and-ratio-word-problems/437042: ok so my question is: How many pieces of popcorn have you eaten if you've had 1/10 of 1/3 of 1/4 of 720 pieces divided by 1/2? 1 solutions Answer 302306 by rfer(12662)   on 2011-04-17 17:40:39 (Show Source): You can put this solution on YOUR website! 720/2=360*.25=90*.333=30*.1=3 pieces

Probability-and-statistics/436784: in an election for school president, the loser recieved 30% of the winner's votes. If 702 votes were cast, how many did each recieve? 1 solutions Answer 302142 by rfer(12662)   on 2011-04-16 21:39:09 (Show Source): You can put this solution on YOUR website! x+0.3x=702 1.3x=702 x=540 0.3x=162

Money_Word_Problems/436760: Tara has a balance of $3892.46 on a credit card with an annual Percentage rate of 16.5%. The minimum payment required on the current statement is $78.00. What is the amount applied to reduce the principal in this payment 1 solutions Answer 302139 by rfer(12662)   on 2011-04-16 21:36:36 (Show Source): You can put this solution on YOUR website! (3892.46*0.165)/12=53.52 78-53.52=$24.48

Numeric_Fractions/436730: Simplify. 4a – b − 4(5a − 7b + 8c) 1 solutions Answer 302138 by rfer(12662)   on 2011-04-16 21:34:03 (Show Source): You can put this solution on YOUR website! 4a-b-20a+28b-32c= -16a+27b-32c

Surface-area/436779: Hey there Tutors,I really need help with this qestion,it makes no sense to me :( QUESTION:It took vincent 104yrds of fencing to enclose a square area around the swimming pool.The length and width of the fencing around the swimming pool are those of the fencing enclosing his square garden.How many yards of fencing are used to enclose his square garden. what iv'e tried: I read.....lol thats pretty much it..I was too confused. 1 solutions Answer 302136 by rfer(12662)   on 2011-04-16 21:30:56 (Show Source): You can put this solution on YOUR website! This really is an easy problem. The swimming pool is a square, you can divide 104 by 4 =26 yds Double 26 to 52 multiply by 4 = 208 yds Or since it says 1/2 just double the amount. This works for perimeter by won't work for area.

Polynomials-and-rational-expressions/436679: t-9=-8 1 solutions Answer 302106 by rfer(12662)   on 2011-04-16 19:51:27 (Show Source): You can put this solution on YOUR website! t=+1