What is the unit digit of the product of all the prime numbers between 51 and 78?

Correct option is C

Given:

Prime numbers between 51 and 78

Formula Used:

The unit digit of a product of expression is the unit place of the product of the unit digits of the numbers

Solution:

Prime numbers between 51and 78 are 53,59,61,67,71,73

The unit place of product of$$53 \times 59 \times 61 \times 67 \times 71 \times 73$$​​

Here we take the product of the unit digits =$$3 \times 9 \times 1 \times 7 \times 1 \times 3 = 567$$​​

Hence 7 will come the unit place of the product