(315+372).3+(372+315).7
[(315+372).3+(372+315).7]:(26.13+74.14)
\(\left(2061+4809\right):1374\)
\(=6870:1374\)
\(=5\)
[(315+372).3+(372+315).7]: (26.13+74.14)[(315+372).3+(372+315).7]: (26.13+74.14)
=[(7+3)(315+372)]:(2.13.13+2.7.74)=[(7+3)(315+372)]:(2.13.13+2.7.74)
= (10.687):[2(13.13+7.74)]= (10.687):[2(13.13+7.74)]
=(10.687):(2.687)=(10.687):(2.687)
=6870:1374=6870:1374
=5
[ ( 315 + 372 ) x 3 + ( 372 + 315 x 7 ] : ( 26 x 13 + 74 x 14 )
[ ( 315 + 372 ) x 3 + ( 372 + 315) x 7 ] : ( 26 x 13 + 74 x 14 )
= [(315 +372)(3 + 7)] : (2.13.13 + 74.7.2)
= [687.10] : [2(169 +518)]
= 6870 : [2.687]
= 6870 : 1374
= 5
tính
A=(315+372).3+(372+315).7
---------------------------------------
26.13+74+14
\(A=\left(315+372\right).3+\left(372+315\right).7\) \(26.13+74+14\)
\(A=\left(315+372\right).\left(3+7\right)\) \(=338+74+14\)
\(A=\left(315+372\right).10\) \(=412+14\)
\(A=687.10=6870\) \(=126\)
1. \(A=\left(315+372\right)\cdot3+\left(372+315\right)\cdot7\)
\(\Rightarrow A=\left(315+372\right)\cdot\left(3+7\right)\)
\(\Rightarrow A=687\cdot10\)
\(\Rightarrow A=6870\)
2. \(26\cdot13+74+14\)
\(=338+74+14=426\)
[ (315 +372 ) . 3 + ( 372 +315 ) . 7 ] : ( 26 .13 + 74 . 14 )
Thực hiện phép tính
tính :
(315 + 372) .3 + (372 + 315) . 7
26 . 13 + 74 . 14
tính A= 1+5+9+......2001
tính B= (315+372). 3+(372+315). 7 : 26. 13+74. 14
A= 1+5+9+.....+2001
Số số hạng: (2001-1):4+1=501
Tổng là: (2001+1)x501:2=501501
Bài 3 : tính nhanh
a) 615+185:5
b) [ (315+372).3+1(372+315).7].(26.13+74.14)
a) 615 + 37 = 652
b) [ (315+372).3+1(372+315).7].(26.13+74.14)
= 687 .3 + 1 . 687 . 7 . (1002 + 1036)
= 687 . ( 3 + 7 ) . 1038
= 687 * 10 . 1038
= 6870 .. 1038
= 7131060
li-ke nha
bai 1: Thuc hien phep tinh
a) B = [ ( 315 + 372 ) . 3 + ( 372 + 315 . 7 ] : ( 26 . 13 + 74 . 14 )
a) B = [ ( 315 + 372 ) . 3 + ( 372 + 315 . 7 ] : ( 26 . 13 + 74 . 14 )
= [687.3+687.7]:1374=6870:1374=5
[(315+372)*3+7*(372+315)]:(26*13+74*13)
mk cần gấp nha