All questions of Multiplication for Class 1 Exam

The shortcut for multiplying a number by 5 when the number is even is to divide the number by 2 to get the tens digit, and the ones digit will always be 0. For example, to multiply 4 by 5, you can divide 4 by 2 to get 2, and the answer is 20.

To find the result of 16 x 5 using the shortcut method, you first multiply the tens digit (1) by 5 to get 5, and the ones digit is always 0. So, the answer is 50. However, don't forget to add the tens and ones digits: 50 + 0 = 50. So, 16 x 5 = 50.

The quickest way to multiply any number by 10 is to simply add 0 to that number. For example, if you want to multiply 3 by 10, you can just add 0 to 3, resulting in 30. This trick works because our number system is based on cycles of ten, making it easy to move each digit one place to the left, effectively multiplying by 10.

Explanation:

The "Amazing Facts of Nine" trick is a mathematical trick that involves multiplying a number by 9 and then observing the resulting digits. This trick can be used to determine certain properties of the original number.

When using this trick, you multiply the original number by 9 and look at the resulting digits of the answer. The tens digit of the answer represents one less than the original number. Let's understand why this is the case.

Working of the Trick:
1. Take any number as the original number.
2. Multiply the original number by 9.
3. Observe the resulting digits of the answer.

Explanation of Option 'C':
According to the given options, the tens digit of the answer represents one less than the original number. Let's see an example to understand this:

Suppose we take the original number as 5.
Multiplying 5 by 9, we get:
5 x 9 = 45

In the answer, the tens digit is 4. Notice that 4 is one less than the original number 5.

Let's take another example with the original number as 8.
Multiplying 8 by 9, we get:
8 x 9 = 72

In the answer, the tens digit is 7. Again, 7 is one less than the original number 8.

We can observe this pattern with any original number. The tens digit of the answer is always one less than the original number.

Conclusion:
Therefore, when using the "Amazing Facts of Nine" trick, the tens digit of the answer represents one less than the original number. This is why option 'C' is the correct answer.

To find the product of 24 x 7 using the chunk method, first, multiply the tens digits (2 and 7) to get 14, and then multiply the ones digits (4 and 7) to get 28. Finally, add these two results together: 14 (tens) + 28 (ones) = 42. So, 24 x 7 = 168.

Explanation:
To multiply a number by 5 when the number is odd, we can follow the given steps:

Step 1: Subtract 1 from the number
When we subtract 1 from any odd number, we get an even number. For example, if the given number is 7, subtracting 1 gives us 6.

Step 2: Divide the result by 2
After subtracting 1, we divide the result by 2. In the previous example, dividing 6 by 2 gives us 3.

Step 3: Final result
The final result is the number obtained after dividing by 2 in step 2. In our example, 3 is the final result.

Explanation in detail:
Let's take an example to understand this concept further. Suppose we have an odd number, let's say 9, and we want to multiply it by 5.

Step 1: Subtract 1 from the number
9 - 1 = 8

Step 2: Divide the result by 2
8 ÷ 2 = 4

Step 3: Final result
The final result is the number obtained after dividing by 2 in step 2, which is 4 in our example.

Verification:
To verify if the final result is correct, we can multiply it by 5 and check if it matches the original odd number.

4 × 5 = 20

The original odd number was 9, and after following the steps, we obtained 20, which is indeed 9 multiplied by 5.

Conclusion:
To multiply a number by 5 when the number is odd, we can subtract 1 from the number and then divide the result by 2. This method ensures that we obtain the correct result without directly multiplying the odd number by 5.

Understanding the "Amazing Facts of Nine" Trick
The "Amazing Facts of Nine" trick helps in quickly calculating the products of numbers multiplied by 9. Let's apply this trick to find the product of 7 x 9.
Step-by-Step Explanation
- Recognize the Trick:
- When multiplying a number by 9, the result can be derived by taking the number (in this case, 7) and subtracting 1, which gives you 6.
- This '6' becomes the first digit of the answer.
- Calculate the Second Digit:
- To find the second digit, subtract 6 (the first digit) from 9 (the total of digits in 9).
- 9 - 6 = 3.
- This '3' becomes the second digit of the answer.
- Combine the Digits:
- Now, combine the two digits you've found: 6 and 3.
- This gives you 63.
Final Result
- Therefore, the product of 7 x 9 is 63, which corresponds to option 'B'.
Conclusion
Using the "Amazing Facts of Nine" trick simplifies and speeds up multiplication, particularly with the number 9. This method not only aids in understanding but also enhances mental math skills, making calculations easier for young learners.

To find the product of 50 x 6 using the shortcut method, first, multiply the tens digits (5 and 6) to get 30, and then multiply the ones digits (0 and 6) to get 0. Finally, add these two results together: 30 + 0 = 30. So, 50 x 6 = 300.

The shortcut for multiplying a number by 9 is to first subtract 1 from the number, and then divide the result by 2. For example, to multiply 8 by 9, subtract 1 to get 7, and then divide by 2 to get 3. So, 8 x 9 = 72.

When you multiply by 3, the pattern for the sum of the digits in the answer is always 3, 6, or 9. For example, when you multiply 6 by 3, the sum of the digits in the answer is 18, and 1 + 8 equals 9.