how do i solve - step by step please - the following?
0.31 = 90x divided by (300 - 60x)
what is x? or rather more importantly, how do i get to the answer?
(the answer is 0.86 tho ive no idea how to get there! help!)
2007-06-12 07:10:15 · 11 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Thanx for the speedy reply sweet - best answer on its way ;)
2007-06-12 07:19:04 · update #1
wow - alot of brainy folk about - thanks to you too!!
2007-06-12 07:20:28 · update #2
0.31 = 90x/(300-60x)
multiply both sides by 300-60x
0.31(300-60x) = 90x
93 - 18.6x = 90x
93 = 108.6x
x = 93/108.6
x = 0.856
2007-06-12 07:16:19 · answer #1 · answered by Astral Walker 7 · 3⤊ 1⤋
Multiply both sides by the (300 - 60x): 0.31*(300 - 60x) = 90x and resolve the parentheses: 93 - 18.6x = 90x, then add the 18.6x to each side: 93 - 18.6x + 18.6x = 90x + 18.6x so: 93 = 108.6x. Then divide each side by the 108.6 to get: 0.856 = x. finally, round it to 2 significant digits (0.31, 90, 60 vs. 300) to get the 0.86 = x answer you already have.
2007-06-12 07:16:44 · answer #2 · answered by roynburton 5 · 1⤊ 1⤋
0.31 = 90x / (300 - 60x)
First: eliminate the fraction - multiply the denominator with each term.
(300-60x)(0.31)=(300-60x)[90x / (300-60x)]
Sec: cross cancel "like" terms & combine the rest.
(300-60x)(0.31)= 90x
*eliminate parenthesis by using Distribution.
(0.31)(300)-(0.31)(60x)= 90x
93-18.6x = 90x
The equation can also be written as...
90x = 93-18.6x
Third: combine "like" terms - add 18.6x with both sides (when you move a term to the opposite side, always use the opposite sign).
90x+18.6x = 93-18.6x+18.6x
108.6x = 93 (divide both sides by 108.6)
(108.6x)/(108.6) = (93)/(108.6)
x = 0.856 (round off to the nearest thousandths)
x = 0.86
2007-06-12 07:23:54 · answer #3 · answered by ♪♥Annie♥♪ 6 · 1⤊ 1⤋
I think what you are asking is to solve the following equation:
0.31 = 90x / (300-60x)
First, we need to multiply each side of the equation by
(300-60x)
This give us 0.31(300 - 60x) = 90x
Multiplying through gives us 93 - 18.6x = 90x
Now, we need to add 18.6x to each side of the equation giving us the following:
93 = 108.6x
Now we divide each side by 108.6 to solve for x.
x = 0.856
2007-06-12 07:17:35 · answer #4 · answered by gavshouse32 1 · 2⤊ 1⤋
0.31=90x/(300-60x) multiply through by 300-60x
0.31(300-60x)=90x
93 - 18.6x= 90x
93 = 108.6x
93/108.6=x=.86
http://www.coolmath.com
2007-06-12 07:18:23 · answer #5 · answered by Anonymous · 1⤊ 1⤋
-multiply both sides by 300-60x: (300-60x) * .31 = 90x
-combine like terms: 93 = 108.6x
- divide 93 by 108.6 to isolate x
- x = .856
2007-06-12 07:16:29 · answer #6 · answered by czwtrpolo2 2 · 1⤊ 1⤋
.31 = 90x/(300 - 60x)
.31 * (300 - 60x) = 90x
93 - 18.6x = 90x
93 = 108.6x
x = 93/108.6 = .856 (rounded to three places)
2007-06-12 07:19:03 · answer #7 · answered by John V 6 · 1⤊ 1⤋
0.31 = 90x/(300 - 60x)
Multiply both sides by (300 - 60x)
0.31(300 - 60x) = 90x
Combine terms and isolate x
93 - 18.6x = 90x
93 = 108.6x
x = 0.856
.
2007-06-12 07:17:23 · answer #8 · answered by Robert L 7 · 1⤊ 1⤋
okay.
.31=90x/300-60x
Times both sides by 300-60x
.31(300-60x)=90x
Multiply 300 & 60x by .31
93-18.6x=90x
Add 18.6 to both sides
93=108.6x
Divide 108.6 from both sides
x=0.8563535
2007-06-12 07:21:06 · answer #9 · answered by michelle7212001 3 · 0⤊ 1⤋
0.31 = 90x / (300 - 60x)
0.31(300 - 60x) = 90x
0.31(300) - 0.31(60x) =90x
93 - 18.6x =90x
90 x+18.6x =93
108.6x = 93
x = 93/108.6
x=0.86
2007-06-12 07:12:33 · answer #10 · answered by sweet n simple 5 · 0⤊ 5⤋