Question

5 What is the difference between the sum of all composite numbers and the sum ofa
prime numbers from 21 to 30?
(1) 176
(2) 203
(3) 205
(4) 215​

Answer 1

Composite Numbers between 21 to 30 are:-

• 22,24,25,26,27,28

Prime Numbers between 21 to 30 are:-

• 23,29

According to Question:

Difference between the sum of all composite numbers and the sum of all prime numbers between 21 to 30.

=(21+22+24+25+26+27+28+30 )-(23+29)

=203-52

=151

• The difference between the sum of all composite numbers and the sum of all prime numbers between 21 to 30 is 151.