FIND SQUARE OF ANY NUMBER ENDING IN 5

To find square of any number ending in 5 follow below two step

E.G. 85*85

STEP-1         Multiply the first digit by the first digit plus one : 8*(8+1)=72

STEP-2         Write the number 25 next to the number from the first step : 7225



Another E.G

45*45
STEP-1  4*(4+1)=20

STEP-2   2025