Question

When we insert 3 rational numbers at equal intervals between 13 and 14, two of the numbers are 13.5 and 13.25. Find the third number.

• A. 13.80
• B. 13.20
• C. 13.66
• D. 13.75

Answer 1

The correct option is D

13.75

Since, we are inserting rational numbers at equal intervals between 13 and 14, we take mean between them (add the 2 numbers and divide the sum by 2).

Between 13 and 14 :

First number = $\frac{13+14}{2}$ = 13.5

Second number = $\frac{13+13.5}{2}$ = 13.25

Third number = $\frac{13.5+14}{2}$ = 13.75

$\therefore$ The required number is 13.75.