Advertisements
Advertisements
Question
If m, n are natural numbers, for what values of m, does 2n × 5m ends in 5?
Advertisements
Solution
2n × 5m
2n is always even for all values of n.
5m is always odd and ends with 5 for all values of m.
But 2n × 5m is always even and ends in 0.
∴ 2n × 5m cannot end with the digit 5 for any values of m.
No value of m will satisfy 2n × 5m ends in 5.
APPEARS IN
RELATED QUESTIONS
A merchant has 120 liters of oil of one kind, 180 liters of another kind and 240 liters of third kind. He wants to sell the oil by filling the three kinds of oil in tins of equal capacity. What should be the greatest capacity of such a tin?
State fundamental theorem of arithmetic.
Find the LCM and HCF of the following integers by applying the prime factorisation method:
24, 15 and 36
Write the exponent of 2 in the prime factorization of 144.
If the prime factorization of a natural number n is 23 × 32 × 52 × 7, write the number of consecutive zeros in n.
Express the number as a product of its prime factor:
3825
Find the LCM and HCF of the following integers by applying the prime factorisation method.
17, 23 and 29
For some integer p, every even integer is of the form ______.
For some integer q, every odd integer is of the form ______.
The largest number which divides 70 and 125, leaving remainders 5 and 8, respectively, is ______.
