Question

only for genius...

$2 = 6 \\ 3 =12 \\ 4 = 20 \\ 5 = 30 \\ 6 = 42 \\ 9 =$
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Answer 1

$\huge\star\underline\mathfrak\purple{Hello \: Omprakash}\star$

$\huge\sf\underline\pink{♡Answer♡}$

If we see the question carefully, one thing is common that the numbers which we are multipliying are increasing in a series.

$\small\sf\underline\green{For \: Example:}$

2 × 3 = 6

3 × 4 = 12

4 × 5 = 20

5 × 6 = 30

6 × 7 = 42

.

.

.

7 × 8 = 56

8 × 9 = 72

.

.

9 × 10 = 90.

Answer 2

$\huge\bigstar\underline\mathfrak\pink{Answer}$

$\huge\boxed{9\:=\:90}$

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$\huge\bigstar\underline\mathfrak\pink{Explanation}$

The Sequence is like :

2 × $\boxed{3}$ = 6

3 × $\boxed{4}$ = 12

4 × $\boxed{5}$ = 20

5 × $\boxed{6}$ = 30

6 × $\boxed{7}$ = 42

7 × $\boxed{8}$ = 56

8 × $\boxed{9}$ = 72

9 × $\boxed{10}$ = 90

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We can see that, if we multiply 2 by 3, we get 6 and then 3 into 4 ......so one.

Lastly, according to the sequence, if we multiply 9 by 10, we get 90.

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Hence,

If, 2 = 6

3 = 12

4 = 20

5 = 30

6 = 42

then, 9 = 90 ( required answer )

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