15 + 5 + 10 + 10 + 202
= (15 + 5) + (10 + 10) + 400
= 20 + 20 + 400
= 440
15 + 5 + 10 + 10 + 202
= 15 + 5 + 10 + 10 + 400
= ( 15 + 5 ) + ( 10 + 10 ) + 400
= 20 + 20 + 400
= 40 + 400
= 440
15+5+10+10+202 =440
k 1 lik e nhe
tính nhanh :
15 + 5 + 10 + 10 + 202
15 + 5 + 10 + 10 + 202
= 15 + 5 + 10 + 10 + 400
= ( 15 + 5 ) + ( 10 + 10 ) + 400
= 20 + 20 + 400
= 40 + 400
= 440