Question

In a five-digit number, the digit at the hundreds place is three-fourth of the digit at ten thousands place and the digit at tens place is two-third of the digit at hundreds place. The digit at tens place is square of the smallest prime number and the digit at thousands place is the largest single digit prime number. If the digit at the unit place is the largest single-digit odd number, then the number is
1. 49327
2. 83419
3. 42937
4. 87649

Answer 1

Correct Answer - Option 4 : 87649

Concept used:

Prime numbers are whole numbers greater than 1, that have only two factors 1 and the number itself

The smallest prime number is 2 and the largest single digit prime number is 7

The largest single-digit odd number is 9

Calculation:

The digit at the unit place is the largest single-digit odd number i.e 9

The digit at tens place is square of the smallest prime number i.e 2² = 4

The digit at tens place is two-third of the digit at hundreds place

The digit at the hundreds place = (3/2) × 4 = 6

The digit at the thousands place is the largest single digit prime number i.e 7

The digit at the ten thousands place = 4/3 × digit at the hundreds place = (4/3) × 6 = 8

Number = 87649

∴ The five-digit number is 87649

Don't find all the number just find unit digit and the tens digit and check the option

Option method is useful in this type of question so go according to the option.