method 1
n . (n+1) = 7482
= 3741 x 2
= 1247 x 2 x 3 x 29 x 43
= 2 x 3 x 29 x 43
= 86 x 87


method 2
find the square root of 7482

use calculator

sq root of 7482
= ‭86.49855490122363888184739

hence, can infer
7482 = 86 x 87


method 3
guess & check

:)


.

At your level guess and check is the best way to go.

Let's try...

5 x 6 = 30

No...the page number cannot be so small.

Let's try 50 x 51 = 2550.

Getting there...

Let's try 100 x 101 = 10100

Too high. The page numbers must be somewhere between 50 and 100.

Let's try 80 x 81 = 6480.

So close...

Let's try 90 x 91 = 8190

Almost there...

Let's try 86 x 87 = 7482

Yes! Success!