Question

How do you simplify $ 8 + 7({4^2} - 3) $ ?

Answer 1

Hint: In this question, we are given some numbers that are in addition, subtraction and multiplication and we have to simplify them, that is, we have to find the number obtained on solving it by applying the given arithmetic operations. First, we will simplify the square of 4; the square of a number is defined as the number obtained when that number is multiplied with itself. On finding the square, we will solve the terms in the parenthesis and then multiply the answer obtained with the term written along with the parenthesis. Then we will apply the arithmetic operation between the terms left in the expression.

Complete step-by-step answer:
Given,
 $ 8 + 7({4^2} - 3) $
Square of 4 is 16, so we get –
 $ 8 + 7(16 - 3) $
On subtracting 3 from 16, we get –
 $ 8 + 7(13) $
Now, 7 is multiplied with 13 and then the resultant number will be added to 8, as follows –
 $
  8 + 91 \\
   \Rightarrow 99 \;
  $
Hence the simplified form of $ 8 + 7({4^2} - 3) $ is $ 99 $ .
So, the correct answer is “ $ 99 $ ”.

Note: In this question, we were given terms in parenthesis, so we know that we have to perform the given operation separately and then with the whole. For example, when we were given $ (20 \div 5)(2 + 3) $ then we divide 20 by 5, and add 2 and 3 separately and then multiply the obtained value and get the answer $ (4)(5) = 20 $ . But in some questions, we are not given a specified order, we will follow the PEMDAS rule for solving those questions. The PEMDAS rule states that we give preference to the arithmetic operations as follows –
Parentheses > Exponents > Multiply or Division > Add or subtract