MCQ Subject: Number System & Arithmetic

A rule to test divisibility by 7: Double the last digit, subtract from the remaining number. If the result is divisible by 7, the original number is too. Applying this to 161:

If HCF of 3/4 and 5/6 is 1/12, what would be the LCM of these fractions?

Two numbers are such that their HCF is 8 and LCM is 420. What is the product of the two numbers?

Which of the following numbers is NOT a perfect square?

In a group of 24 students, the ratio of students who prefer Mathematics to those who prefer Physics is 7:3. If the HCF of the number of students who prefer Mathematics and Physics is 7, find the number of students who prefer Physics.

In the number 54,219, what is the place value of the digit ‘9’?

The HCF and LCM of two numbers are 15 and 105 respectively. If the smaller number is 15, what is the larger number?

A number is divisible by 6 if it is divisible by both 2 and 3. What is the least number that is 15 times a multiple of 6 but not a multiple of 9?

Identify the next number in the sequence: 3, 5, 8, 11, 14, 19, ___

What is the highest common factor (HCF) of 48 and 18?