m is what %?

[mjjking]

Hi guys,

this is from OG10. Can you explain if there is a different way to approach? How do I backsolve this?

thanks!

"If m>0 and x is m percent of y, then, in terms of m, y is what percent of x?

a. 100m
b. 1/(100m)
c. 1/m
d. 10/m
e. 10000/m

thanks!

OA is E

[shulapa]

The way to solve this is to know how to change from from fractions to percentage.

if A [%] = A/100 so B = 100B [%].

Lets apply this idea to the question:

Y = X*m[%] = X*m/100

Therefore,

X=Y*100/m.

The answer needs to be in percentage, so we need to change again.

if B = 100/m so B[%] = 100*100/m = 10000/m.

Actually when looking at the question now I see that it was even easier to solve it by plugging numbers:

lets assume that X = 1 And Y = 10, so X is ten percent of Y and m is 10.
However, Y is 1000 percent of X. so only E gives this ratio.

Hope this helps.

Eyal

[Tryingmybest]

x% means X/100

x= (m/100) y

=> y = ( 100/m) x
= ( 100 * 100)/(100*m) x ---- I multiplied and divided by 100
=( 10000/m* 100) x
= 10000/m % x

E

[kanha81]

Hi guys,

this is from OG10. Can you explain if there is a different way to approach? How do I backsolve this?

thanks!

"If m>0 and x is m percent of y, then, in terms of m, y is what percent of x?

a. 100m
b. 1/(100m)
c. 1/m
d. 10/m
e. 10000/m

thanks!

mjjking-

Backsolving is a good approach; however, the way I have learned to solve different problems differently, for me, this problem does not fit that criteria. However, this is how I was able to solve it in less than a minute. Hope it helps!

x = (m/100) * y
=> y = (100*x) / m

y = (p/100) * x, where p is unknown percent
=> (100*x) / m = (p/100) * x
=> p = 10000/m (b/c- x cancels out)

Hence [E]