Practice Multiplying by 5, 25, 125, and 625

Introduction

This worksheet helps learners practice fast multiplication by 5, 25, 125, and 625 using efficient left-to-right mental arithmetic tricks. These shortcuts replace long multiplication with simple halving and division steps, significantly improving speed and accuracy.

The Core Idea Behind This Trick

The numbers 5, 25, 125, and 625 are closely connected to powers of 2. By appending zeros and then dividing by 2, 4, 8, or 16, multiplication becomes a much simpler mental operation.

This approach aligns naturally with left-to-right thinking and builds directly on halving skills developed in earlier quick arithmetic practice.

Configurable Worksheet Options

This is a configurable, online worksheet that allows learners to adjust the difficulty level before generating problems.

• Select the number of digits for the multiplicand: 2, 3, 4, or 5
• Choose to exclude the digits 0 or 1 for added challenge

Each configuration produces a fresh set of problems, making the worksheet ideal for repeated speed practice.

Multiply by 5

To multiply a number by 5, append one zero to the multiplicand and halve the result.

• Append 1 zero
• Divide by 2
• Example: 56 5 → 560 2 = 280

Multiply by 25

To multiply a number by 25, append two zeros to the multiplicand and divide by 4 (or halve the number twice).

• Append 2 zeros
• Divide by 4
• Example: 729 25 → 72900 4 = 18225

Multiply by 125

To multiply a number by 125, append three zeros to the multiplicand and divide by 8 (or halve the number three times).

• Append 3 zeros
• Divide by 8
• Example: 634 125 → 634000 8 = 79250

Multiply by 625

To multiply a number by 625, append four zeros to the multiplicand and divide by 16 (or halve the number four times).

• Append 4 zeros
• Divide by 16
• Example: 217 625 → 2170000 16 = 135625

Left-to-Right Mental Strategy

All calculations should be performed mentally from left to right. Learners should visualize the appended zeros first and then apply the division step smoothly using place-value reasoning.

This avoids mechanical long multiplication and keeps the thinking fast, clean, and structured.

Related Worksheets

Before practicing these multiplication tricks, learners are encouraged to strengthen their halving skills.

• Practice Halving and Doubling the Numbers
• Halving and Doubling Number Towers

The halving techniques developed in those worksheets apply directly to multiplying by 5, 25, 125, and 625.

Online, Interactive, and Self-Correcting

This is an online, interactive worksheet where learners enter only the final product into the input box.

Answers are checked instantly, allowing immediate feedback and correction. No printing or downloading is required.