When 7179 and 9699 are divided by another natural number N , remainder...
We are given that when 7179 and 9699 are divided by a natural number N, the remainder obtained is the same. This means that 7179 - 9699 must be divisible by N.
First, calculate the difference between 9699 and 7179:
9699 - 7179 = 2520
Now, we need to find the divisors of 2520 that end with one or more zeros. ie multiples of 10.
Step 1: Find the divisors of 2520.
2520 = 2^3 × 3^2 × 5 × 7
l number of divisors is given by the product of one plus each of the exponents in the prime factorization:
(3 + 1) × (2 + 1) × (1 + 1) × (1 + 1) = 4 × 3 × 2 × 2 = 48
So, 2520 has 48 divisors in total.
Step 2: Find divisors of 2520 that are multiples of 10
.To be a multiple of 10, the divisor must include at least one factor of 2 and one factor of 5.
From the prime factorization of 2520, we know that there are 3 factors of 2 and 1 factor of 5, so the divisors of 2520 that are multiples of 10 must include at least one 2 and one 5.
the remaining factors after we take out one factor of 2 and one factor of 5 from the prime factorization of 2520:
2520 / 10 = 2^2 × 3^2 × 7
The number of divisors of 2^2 × 3^2 × 7 is:
(2 + 1) × (2 + 1) × (1 + 1) = 3 × 3 × 2 = 18
So, there are 18 divisors of 2520 that are multiples of 10.
Step 3: Conclusion The number of values of N that end with one or more zeros is 18.
Thus, the correct answer is:
c) 18.