Question

If 35% of a number is 77 and 90% of the same number is 198, find 55% of that number.

Answer 1

121

Explanation:

Because one of the answers is already divisible by 10, allowing us to find 100% of the unknown number, we can first find 10% by dividing the 90% number by 9. 198/9 is 22, meaning 22 is 10% of the number. We can then multiply it by 10 to get 100%, 22(10)=220. Meaning our full number is 220

From here we can simply multiply by our desired percentage, which is 55%. In order to multiply by a percent, you have you divide the percent by 100 to get .55. From there you can do 220*.55= 121. Meaning our answer is 121.

Answer 2

Let's call the number we're trying to find "x".

We know that 35% of x is 77, so we can set up the equation:

0.35x = 77

We also know that 90% of x is 198, so we can set up another equation:

0.9x = 198

We can use the first equation to find the value of x and then substitute that value into the second equation to find 55% of x.

To find x, we divide both sides of the first equation by 0.35:

x = 77 / 0.35 = 220

Now that we know x is 220, we can find 55% of x by multiplying 220 by 0.55:

0.55x = 220 * 0.55 = 121

So 55% of the number is 121.