When you multiply fractions you want to make them a mixed number then multiply the two top numbers together and then the bottom two together. Basically 6 2/3 would become 20/3 x 5/6... then multiply 5 and 20 together and 3 and 6 together to get 100/18... simplify from there.
Answer:
Option (b) is correct.

Step-by-step explanation:
Given expression "four times the square of a number is thirty-six"
We have to write it mathematically and choose the correct options out of given options.
Consider the given expression "four times the square of a number is thirty-six"
Then
let the number be x ,
Then four times the square of a number written mathematically as 
And given "four times the square of a number is thirty-six" written mathematically as 
Therefore, "four times the square of a number is thirty-six" written mathematically as 
Option (b) is correct.
The first step will be to add 6 on both sides