69*24=?
12*76=?
Tính nhanh:
a) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
b) 583 x 931 + 69 x (170 + 583) + 31 x 170
c) 732 x 976 + 24 x (680 + 732) + 76 x 680
\(a,2\times31\times12+4\times6\times42+8\times27\times3\)
\(=24\times31+24\times42+24\times27\)
\(=24\times\left(31+42+27\right)\)
\(=24\times100\)
\(=2400\)
\(b,583.931+69.\left(170+583\right)+31.170\)
\(=583.931+69.170+69.583+31.170\)
\(=583.\left(931+69\right)+170.\left(69+31\right)\)
\(=583.1000+170.100\)
\(=583000+17000\)
\(=600000\)
\(c,732.976+24.\left(680+732\right)+76.680\)
\(=732.976+24.680+24.732+76.680\)
\(=732.\left(976+24\right)+680.\left(24+76\right)\)
\(=732.1000+680.100\)
\(=732000+68000\)
\(=800000\)
Học tốt
a)2400
b)600000
c)800000
a) 2 x 31 x 12 + 4 x 6 x 42 + 8 x 27 x 3
= 24 x 31 + 24 x 42 + 24 x 27
= 24 x ( 31 + 42 + 27 )
= 24 x 100
= 2400
b) 583 x 931 + 69 x ( 170 + 583 ) + 31 x 170
= 583 x 931 + 69 x 170 + 69 x 583 + 31 x 170
= 583 x ( 931 + 69 ) + 170 x ( 69 + 31 )
= 583 x 1000 + 170 x 100
= 583000 + 17000
= 600000
c) 732 x 976 + 24 x ( 680 + 732 ) + 76 x 680
= 732 x 976 + 24 x 680 + 24 x 732 + 76 x 680
= 732 x ( 976 + 24 ) + 680 x ( 24 + 76 )
= 732 x 1000 + 680 x 100
= 732000 + 68000
= 800000
a, 45 x 76 + 90 x 12
b, 2 x 31 x 12 + 4x6 x 69
c, 36 x 28 + 36 x 82 + 64 x 69 + 64 x 41
d, 156 ( x + 61 ) = 82
a) 45 x 76 + 90 x 12
= 45 x 76 + 45 x 2 x 12
= 45 x 76 + 45 x 24
= 45 x ( 76 + 24 )
= 45 x 100
= 4500
b) 2 x 31 x 12 + 4 x 6 x 69
= 24 x 31 + 24 x 69
= 24 x ( 31 + 69 )
= 24 x 100
= 2400
c) 36 x 28 + 36 x 82 + 64 x 69 + 64 x41
= 36 x ( 28 + 82 ) + 64 x ( 69 + 41 )
= 36 x 110 + 64 x 110
= 110 x ( 36 + 64 )
= 110 x 100
= 11 000
d) 156 ( x + 61) = 82
=> x + 61 = \(\frac{82}{156}\)
=> x + 61 = \(\frac{41}{78}\)
=> x = \(\frac{41}{78}\)- 61
=> x = \(\frac{-4717}{78}\)
45 x 76 + 90 x 12 = 45 x 76 + 45 x 2 x 12
= 45 x 76 + 45 x 24
= 45 x (76 + 24)
= 45 x 100
= 4500
b) 2 x 31 x 12 + 4 x 6 x 69 = 62 x 12 + 2 x 12 x 69
= 62 x 12 + 138 x 12
= (62 + 138) x 12
= 200 x 12 = 2400
a, 45 x 76 + 90 x 12
= ( 45 x 12 ) + ( 76 x 90 )
= 540 + 6840
= 7 380
c,
= 36 x ( 28 + 82 ) + 64 x ( 69 + 41 )
= 36 x 110 + 64 x 110
= 110 x ( 36 + 64 )
= 110 x 100
= 11000
g) (15 + 37) + (52 – 37 – 17) h) (38 – 42 +14) - (38 – 42 - 15) i) (27 + 65 ) + (346 - 27- 65) k) - (27 + 65) - (346 – 27 - 65) l) (42 – 69 + 17) - (42 + 17) m) 24. (16 - 5) – 16. (24 – 5 ) n) (-12). 47 – 12 . 52 + (-12) p) 51 . (69 - 25) – 69. (51 - 25) |
g) (15 + 37) + (52 – 37 – 17) = 15 + 37 + 52 – 37 – 17 = 15 + 52 – 17 = 50 h) (38 – 42 +14) - (38 – 42 - 15) = 38 – 42 +14 - 38 + 42 + 15 = 14 + 15 = 29 i) (27 + 65 ) + (346 - 27- 65) = 27 + 65 + 346 - 27- 65 = 346 k) - (27 + 65) - (346 – 27 - 65) = -27 - 65 - 346 + 27 + 65 = -346 l) (42 – 69 + 17) - (42 + 17) = 42 – 69 + 17 - 42 - 17 = – 69 m) 24. (16 - 5) – 16. (24 – 5 ) = 24. 16 - 24 . 5 - 16 . 24 + 16. 5 = - 24 . 5 + 16. 5 = -8 . 5 = -40 n) (-12). 47 – 12 . 52 + (-12) = -12 (47 - 52 + 1) = -12 . (-4) = 48 p) 51 . (69 - 25) – 69. (51 - 25) = 51 . 69 - 51 . 25 – 69. 51 + 69. 25 = - 51 . 25 + 69. 25 = (- 51+ 69).25 = 450 |
Tính nhanh:
12 + 24 + 88 + 76 + 100
Đáp án:
12 + 24 + 88 + 76 + 10
= ( 12 + 88 ) + ( 24 + 76)
= 100 + 100
= 200
Bỏ ngoặc rồi tính
a, (367 - 24 ) + ( 133 - 76 )
b, ( 25 + 38 + 12 ) + ( 1022 - 12 )
a: =367-24+133-76
=500-100
=400
Tính nhanh : 12 x 24 + 12 x 76
36+25+12+69+25+24
số đó là
350
mong các bn
ủng hộ cho mình
cảm ơn nhìu
12+99+88+1+35+24+65+76=
12+99+88+1+35+24+65+76
=(12+88)+(99+1)+(35+65)+(24+76)
=100+100+100+100
=400
12 + 99 + 88 + 1 + 35 + 24 + 65 + 76
= ( 99 + 1 ) + ( 88 + 12 ) + ( 35 + 65 ) + ( 76 + 24 )
= 100 + 100 + 100 + 100
= 400
12+99+88+1+35+24+65+76=400
CHÚC BẠN HỌC TỐT
Tính các tổng sau bằng phương pháp hợp lí nhất:
C=3/4*7+3/7*10+3/10*13+...+3/73*76
D=7/10*11+7/11*12+7/12*13+...+7/69+70