Question

3x2=7 , 5x4=23 , 7x6=47 , 9x8=79 , 10x9=?

Answer 1

3²-2=7
5²-2=23
7²-2=47
9²-2=79
10²-2=98

Answer 2

Answer:

The value of 10 ×9 in the series is 99.

To find:

The value of 10×9 in the given series  

Solution:

Here the series is formed by the multiplication of two numbers x and x-1.  

The resultant of the series will be the multiplication of the given two numbers along with the addition of the number 1.

$\begin{array} { r } { 3 \times 2 = 7 , [ ( 3 \times 2 ) + 1 = 7 ] } \\\\ { 5 \times 4 = 23 , [ ( 5 \times 4 ) + 3 = 23 ] } \\\\ { 7 \times 6 = 47 , [ ( 7 \times 6 ) + 5 = 47 ] } \\\\ { 9 \times 8 = 79 , [ ( 9 \times 8 ) + 7 = 79 ] } \\\\ { 10 \times 9 = [ ( 10 \times 9 ) + 9 ] = 90 + 9 = 99 } \end{array}$

The value of 10 ×9 in the series is 99.