Number System

high importance~2 Q in Tier 133 formulas⚡ 18 shortcuts6 subtopics

Exam-level questions worked step by step. Try each one yourself first — then expand the solution and compare routes.

Q1.

What is the unit digit of $3^{65} \times 6^{59} \times 7^{71}$ ?

Q2.

What is the remainder when $25^{25}$ is divided by 9?

Q3.

Which of the following fractions is the largest? $\frac{5}{7}, \frac{7}{10}, \frac{9}{13}, \frac{11}{16}$

Q4.

The expression $3^{25} + 3^{26} + 3^{27} + 3^{28}$ is divisible by which of the following?

Q5.

What is the sum of all two-digit numbers that are divisible by 6?