Compute the following differences:

(124 × 76) – (126 × 74)

(124 × 76) can be written as (100+24)(100-24)

using identity -

(100+24)(100-24) = -

= 10000 - 576

= 9424

now (126 × 74) can be written as (100+26)(100-26)

using identity -

(100+26)(100-26) = -

= 10000 - 676

= 9324

now putting values in question

(124 × 76) – (126 × 74) = 9424-9324

= 100