a. 13
b. 24
c, 20
d. 9
Now the real challenge is can you see how these are mental math all based off finding 10% of a number? Look at my answer to "a".. can you see that finding 10% of a number is equivalent to just shifting the decimal point to the left one place. This can be helpful for all the other problems.
For 'b', 30% of a number is just 3 times 10%
For 'c', since we want 80% of 25, we can just subtract 20% or 2 times 10% of 25 away.
For 'd', 15% is just 10% + 5% or 6 + 3 note once you find 10% of 60 to be 6, just take half of 6 to get 5%...Awesome..
Now go get those percent problems... Hope this helped
