99
9798
×49.
分析:根據(jù)數(shù)字特點(diǎn),把99
97
98
拆成(99+
97
98
),然后運(yùn)用乘法分配律寫成99×49+
97
98
×49,再把99看作(100-1),計(jì)算得出結(jié)果.
解答:解:99
97
98
×49,
=(99+
97
98
)×49,
=99×49+
97
98
×49,
=(100-1)×49+
97
2
,
=4900-49+48
1
2
,
=4900-49+48+
1
2
,
=4900-1+
1
2
,
=4899
1
2
點(diǎn)評:此題考查了學(xué)生根據(jù)數(shù)字特點(diǎn)進(jìn)行靈活簡算的能力.
練習(xí)冊系列答案
相關(guān)習(xí)題

同步練習(xí)冊答案