Tính hợp lí
a,15.(27+ 18 +6 ) + 15.( 23 +12)
= 15(27+18+6+23+12)
= 15.86
= 1290
b,24.(15 + 49 ) + 12. ( 50 + 42 )
=12.2(15+49)+12.(50+42)
= 12(30+98)+12(50+42)
=12(30+98+50+42)
=12.220
= 2640
c,53.(51+4)+53.(49+96) +53
=53(51+4)+53(49+96)+53.1
=53(51+4+49+96+1)
=53.201
=10653
d,42.( 15 +96) +6.(25 +4).7
=42(15+96)+42(25+4)
=42(15+96+25+4)
=42.140
=5880
tick đúng cho mk nha pikachu
Tính hợp lí:
\(a)\)\(15.\left(27+18+6\right)+15.\left(23+12\right)\)
\(=\)\(15.51+15.35\)
\(=\)\(15.\left(51+35\right)\)
\(=\)\(15.86\)
\(=\)\(1290\)
\(b)\)\(24.\left(15+49\right)+12.\left(50+42\right)\)
\(=\)\(24.64+12.92\)
\(=\)\(1536+1104\)
\(=\)\(2640\)
\(c)\)\(53.\left(51+4\right)+53.\left(49+96\right)+53\)
\(=\)\(53.55+53.145+53\)
\(=\)\(53.\left(145+55+1\right)\)
\(=\)\(53.201\)
\(=\)\(10653\)
\(d)\)\(42.\left(15+96\right)+6.\left(25+4\right).7\)
\(=\)\(42.\left(15+96\right)+42.\left(25+4\right)\)
\(=\)\(42.111+42.29\)
\(=\)\(42.140\)
\(=\)\(5880\)
