Toán Lớp 6: 1.thực hiện phép tính a,31.65+31.35-500 b,4.5 mũ 2 -81:3 mũ 2 c,2 mũ 2.25.17+5.20.27+10 mũ 2 . 5 mũ 6 d,132-[16-(132-128)mũ 2] e,{46-[

Question

Toán Lớp 6:  1.thực hiện phép tính a,31.65+31.35-500 b,4.5 mũ 2 -81:3 mũ 2  c,2 mũ 2.25.17+5.20.27+10 mũ 2 . 5 mũ 6 d,132-[16-(132-128)mũ 2] e,{46-[(16+71.4):15]}-2 g,120:{300[150-(2.5 mũ 3 -2 mũ 3 .25)]}

quynhmaithu · Answer

a,31.65+31.35-500     = 31.(65+35)-500     = 31.  100 - 500     = 3100-500     = 2600     b) 4. 5&sup2; - 81:3&sup2;     = 4. 25 - 81 : 9     =  100 - 9     =   91     c) 2&sup2;. 25 .17 +5.20.27+10&sup2;.5^6     = 4 . 25 .17 +5.20.27+100.15625     = 100 .17 + 100 .27 +1562500     =   1700 + 2700 + 1562500     =        4400 +1562500     = 1566900     d),132-[16-(132-128)&sup2;]     =132-[16-4&sup2;]     = 132-[16-16]     = 132-0     =132     e) {46:[(16+71.4):15]}-2     = { 46 : [(16 + 284):15]} - 2     = {46 : [300:15} - 2     = {46 : 20} -2     =2,3 - 2     = 0,3     g,120:{300[150-(2.5&sup3; -2&sup3;. 25)]}     =120:{300[150-(2. 125-2&sup3;.25)]}     =120:{300[150-( 250-8 .25)]}     = 120:{300[150- ( 250-200)]}     =120:{300[150- 50]}     = 120:{300. 100}     = 120: 30000     =  0,01

minhtuquynh · Answer

1. thức hiện ph&eacute;p t&iacute;nh   a,31.65+31.35-500      = 2015+1085-500      = 1286-500      = 786   b,4.$5^{2}$-81&divide;$3^{2}$       = 100-9      = 91   c,$2^{2}$.25.17+5.20.27+$10^{2}$.$5^{6}$       = 1700+2700+1562500      = 1566900   d,132- [$16-(132-128)^{2}$  ]        = 132-[16-$4^{2}$]        = 132     e,{46-[(16+71.&divide;  15]}-2         = {46-20}-2         = 26-2         = 24     g,120&divide;{300[150-($2.5^{3}$-$2^{3}$.25)]}         = 120&divide;{300[150-50]}         = 120&divide;{300.100}         = 120&divide;30000         = $ frac{1}{250}$