Simple method of 35 × 35 + 65 × 35

Simple method of 35 × 35 + 65 × 35


35×35+65×35
=(35+65)×35
=100×35
=3500



123+123+159+4567+49867+487498x948748x2485=?





Who can help me solve the problem of "comparing the scores of 123 / 456 and 1234 / 4567",


Or with a calculator, I haven't thought of any clever method at present