Answer:
21
Step-by-step explanation:
There are 2 halfs in 1 number.
Lets start with your whole number: 10
You double 10 because there are two halfs in each whole number making it equal 20.
Now you have 3/4
There would be 1 half in this number because it's a fraction and not a whole number.
You would be left over with 1/4
Your answer is 21
Hope this helps! Goodluck
