if 2/5 = a/40, then a =?
thanks!
2007-03-08 17:16:37 · 8 answers · asked by lndsuedelvr 2 in Science & Mathematics ➔ Mathematics
please explain how you solve this problem, not just the answer...thanks!
2007-03-08 17:19:52 · update #1
16
2007-03-08 17:18:33 · answer #1 · answered by Bob R. 6 · 0⤊ 1⤋
Since 40 is in the denominator, you can multiply both sides of the equation by 40, and your "a" will be left alone on one side of the equal sign. The whole point is to get "a" by itself.
After multiplying 2/5 by 40, you should have 16.
Now your equation says 16 = a, which is your answer.
2007-03-09 01:25:35 · answer #2 · answered by Mystery Viscera 2 · 0⤊ 0⤋
You cross multiply. 40 X 2 = 80 divided by 5 = 16.
2007-03-09 01:20:34 · answer #3 · answered by Joe 5 · 0⤊ 0⤋
By multiplying both sides of the equation by the greatest common denominator, in this case 40.
2/5 x 40 = a/40 x 40
16 = a
2007-03-09 01:22:44 · answer #4 · answered by netthiefx 5 · 0⤊ 0⤋
a=80/5 =16
2007-03-09 01:19:17 · answer #5 · answered by pookie 1 · 0⤊ 0⤋
can you see the relation there? 5 x 8 = 40, so, 2 x 8 = 16...that's an easy explanation!
2007-03-09 01:19:45 · answer #6 · answered by Isabel 2 · 0⤊ 0⤋
2/5=a/40
or, 5a=80 [by cross-multiplication]
a=80/5=16
Another process
Multiplying both sides by 40 we get
40*2/5=40*a/40
=>16=a [after reducing]
2007-03-09 01:23:10 · answer #7 · answered by alpha 7 · 0⤊ 0⤋
5x 8 =40
2x8=16
2007-03-09 01:19:21 · answer #8 · answered by pups 5 · 0⤊ 0⤋