Tính bằng cách hợp lí nhất a) 173 + (−46) + (−54) + (+27) + (−19); b) (−62)
Giải thích
1. 173 + (−46) + (−54) + (+27) + (−19) = (173 + 27) + (−46 − 54) + (−19) = 200 + (−100) + (−19) = 81.
2. (−62) + (+1523) + (−38) + (−2523) + (−92) = [(−62) + (−38)] + [1523 + (−2523)] + (−92) = −1192.