In this case, 'n' is used in place of the word 'number'. 'Product' refers to multiplication, so we multiply n by 7. 3 LESS refers to subtraction, so we subtract 3 from 7n. Then, we know that the solution to that is four more than what the actual number is. MORE refers to addition, so we add 4 to n.
The formula to find the surface area of a circle is: pi x radius², so if we square the radius the answer would be 25, then we multiply that by 3.14 and the answer would be around 78.5, so the answer is 78.5.
