Making the assumption that your problem looks like this,

we use the distributive property to multiply:
This statement is correct as 12 is half of 24 and 2 is half of 4. We can also put this as the fraction 1/2 or 0.5 or 50% or 1:2. Therefore for every one bot there are two girls in the class.
Answer:
150 miles
Step-by-step explanation:
If 1/2 of an inch is 20 miles, we can assume that 1/4 of an inch is 10 miles, since half of 1/2 is 1/4 and 1/2 of 20 is 10.
Equipped with this information, we can divide 3 by 1/2 or multiply 3 by the reciprical, 2/1 to get how much we should multiply 20 by.
3*2=6
20*6=120
Then we can multiply 10 by 3 and add that on our answer, since there are still 3/4s left and 1/4=10 miles.
10*3=30
120+30=150
The actual distance is 150 miles.
Hope this helps!
A is the answer sir if I’m wrong I’m sorry but I’m sure