Test: Elephants, Tigers, and Leopards - Class 4 MCQ

In addition tables, the behaviour of even and odd sums can be summarised as follows:

• Odd rows can produce both even and odd sums.
  

In an addition table, each row adds the row number to the column number.

This means that as you move across a row, each number is the sum of the row and column indices.

This pattern is consistent and makes option B correct.

To solve the problem of reversing and adding the number 39:

• Start with the number 39.
• Reverse its digits to get 93.
• Add 39 and 93 together.
• The sum is 132.

Thus, the result is 132.

When you add an odd number to another odd number, the result is always an even number.

The solution involves checking which pairs of numbers, when reversed and added together, result in a sum of 55. The pairs are:

• 23 and 32: Reverse each number and add them to get 55.
• 50 and 05: Reverse each number and add them to get 55.
• 14 and 41: Reverse each number and add them to get 55.

Thus, the correct answer is all of the above.

The pattern seen on the diagonal of an addition chart consists of even numbers.

This is because:

• Each number on the diagonal is the sum of the same number added to itself.
• For example, adding 1 to 1, 2 to 2, and so on results in 2, 4, 6, 8, etc.
• These sums are all even numbers since any number added to itself is even.

To make the number 9 using an addition chart, there are 5 different combinations. These are:

• 0 + 9
• 1 + 8
• 2 + 7
• 3 + 6
• 4 + 5

19 + 91 = 100 → This is the smallest 3-digit number you can get by reversing and adding.

So, the answer is 100.

To find which pair results in a sum of 110 using the "Reverse and Add" method, follow these steps:

• Start with each number in the pair.
• Reverse the digits of each number.
• Add the reversed numbers together.

For pair D: 28 and 82:

• Reverse of 28 is 82.
• Reverse of 82 is 28.
• Add them: 82 + 28 = 110.

Therefore, the correct pair is D.

Even rows yield even sums when added with even columns (e.g., 2 + 2 = 4), and odd sums with odd columns (e.g., 2 + 3 = 5). This illustrates the relationship between odd and even numbers in addition. Understanding these properties helps students grasp the foundational elements of arithmetic, leading to better comprehension of mathematical concepts. Interestingly, the interplay of odd and even numbers is not only a fundamental aspect of mathematics but also extends into various fields such as computer science and coding.