What’s the missing number?
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Step-by-step explanation:
Notice that:
1st column = (5 - 1)² = 16
2nd column = (11 - 4)² = 49
Therefore 3rd column = (18 - *)² = 121, * = 7.
Answer:
7 is the missing number
Step-by-step explanation:
Let the missing number be x.
Lets study the pattern of the numbers. In each column , we find that the bottom number is the square of the difference of first 2 numbers.
In 1st column ,
Difference of first 2 numbers = 5 - 1 = 4
The bottom number = 16 = 4²
In 2nd column ,
Difference of first 2 numbers = 11 - 4 = 7
The bottom number = 49 = 7²
Similarly ,
Difference of first 2 numbers = 18 - x
The bottom number = 121
[tex] = > {(18 - x)}^{2} = 121[/tex]
[tex] = > {(18 - x)}^{2} = {11}^{2} [/tex]
[tex] = > 18 - x = 11[/tex]
[tex] = > x = 18 - 11 = 7[/tex]