Question 7
Use the same rule to fill these pyramids:
In these number pyramids, each block's number is found by adding the numbers in the two blocks directly below it.
Step 1 — Fill Pyramid (i)
We need to find the number in the top block. This number is the sum of the two numbers below it.
Step 2 — Fill Pyramid (ii)
First, we find the numbers for the middle row. The left block in the middle row is the sum of 3 and 4.
The right block in the middle row is the sum of 4 and 3.
Now, we find the number for the top block. This number is the sum of the two numbers in the middle row (7 and 7).
Step 3 — Fill Pyramid (iii)
Let us start by filling the second row from the bottom. The first block is the sum of 5 and 4.
The second block is the sum of 4 and 5.
The third block is the sum of 5 and 0.
Now, we fill the third row from the bottom. The first block is the sum of the first two numbers in the second row (9 and 9).
The second block is the sum of the second and third numbers in the second row (9 and 5).
Finally, we find the number for the top block. This number is the sum of the two numbers in the third row (18 and 14).
Answer
(i) The top number is 8. (ii) The numbers in the middle row are 7 and 7. The top number is 14. (iii) The numbers in the second row are 9, 9, and 5. The numbers in the third row are 18 and 14. The top number is 32.
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