Question

Which of the following statement(s) is/are TRUE?
I. The total number of positive factors of 72 is 12.
II. The sum of first 20 odd numbers is 400.
III. Largest two digit prime number is 97.

A) Only I and II B) Only II and III C) Only I and III D) All are true.

Answer 1

Answer:

1) false

2) true

3) true

Step-by-step explanation:

b) Only 2 and 3

Answer 2

Answer:

The Answer is D

Step-by-step explanation:

1.When we will see the factor of 72 they will be 2*2*2*3*3

Which will be equal to 2^3*3^2

here we will multiply the power of both factors by adding one to both powers

4*3=12

Note:- We are adding one to the power because 2^0 and 3^0 is also there in 2^3 and 3^2

2.Here 1 digit is 1 and last digit is 39 and n is 20 and by applying formula of Sn=n/2(a+l) where a is 1st digit and l is last digit and after solving it we will get 20/2(39+1)=400

3.Largest 2 digit prime is 97 it is true because 99 and 98 has more than 2 factors which are 2 digits number more than 97 where 97 has only 2 factors