Question

How do you evaluate $13 \times 5 - 4 \times 7 + 7$?

Answer 1

Hint: The given expression consists of a number of the mathematical operators such as multiply, addition and subtraction, so here we will apply the DMAS rule. According to DMAS rule, first Division, multiplication, addition and subtraction are applied.

Complete step by step answer:
Take the given expression: $13 \times 5 - 4 \times 7 + 7$
According to DMAS rule, first apply Division, multiplication, addition and subtraction. So, here will apply multiplication.
$ = \underline {13 \times 5} - \underline {4 \times 7} + 7$
Simplify the above expression –
$ = 65 - 28 + 7$
Now perform addition in the above expression –
$ = 65 - 35$
Simplify the above expression –
$ = 30$
Therefore, the required solution is –
$13 \times 5 - 4 \times 7 + 7 = 30$

Note: Be careful while simplification of these types of sums, always follow the same pattern DMAS. Remember and be careful about the sign convention.
Be careful about the sign while doing simplification and remember the golden rules-
Addition of two positive terms gives the positive term
Addition of one negative and positive term, you have to do subtraction and give signs of bigger numbers, whether positive or negative.
Addition of two negative numbers gives a negative number but in actual you have to add both the numbers and give a negative sign to the resultant answer.
Product of two positive terms gives resultant value in positive.
Product of two negative terms gives resultant value in positive.
Product of one positive and one negative term gives value in negative.