Question

Evaluate the following products without multiplying directly
A) 202×198​

Answer 1

Answer:

202×198= 3996

Step-by-step explanation:

$202 = (200 + 2)$

$198 = (200 - 2)$

The two equations are similar to the "difference of two square" which is:

${x}^{2} - y ^{2} = (x + y)(x - y)$

So, by letting x=200 and y=2,

$( {200}^{2} - {2}^{2} ) = (200 + 2)(200 - 2)$

$40000 - 4 = 39996$