Tính nhanh :
(145 x 99 + 145) - (143 x 102 - 143 x 2) + 54 x 47 - 47 x 53 - 20 -27
Tính nhanh
(145 x 99 + 145 ) - ( 143 x 102 – 143 × 2 ) + 54 x 47 - 47 x 53 - 20 - 27
(145 x 99 + 145 ) - ( 143 x 102 – 143 × 2 ) + 54 x 47 - 47 x 53 - 20 - 27
= 145 × (99 + 1) – 143 × (102 – 2) + 47 × (54 – 53) – (20 + 27)
= 145 × 100 – 143 × 100 + 47 × 1 – 47
= 100 × (145 – 143) + (47 – 47)
= 100 × 2 + 0
= 200
Tính nhanh (145 x 99 + 145 ) - ( 143 x 102 – 143 × 2 ) + 54 x 47 - 47 x 53 - 20 - 27
(145 x 99 + 145 ) - ( 143 x 102 – 143 × 2 ) + 54 x 47 - 47 x 53 - 20 - 27
= 145 × (99 + 1) – 143 × (102 – 2) + 47 × (54 – 53) – (20 + 27)
= 145 × 100 – 143 × 100 + 47 × 1 – 47
= 100 × (145 – 143) + (47 – 47)
= 100 × 2 + 0
= 200
Tính nhanh
A, (145 x 99 + 145 ) - (143 x 102 -143)
B, 54 x 47 x - 47 x 53 - 20 -27
A) 145 x (99 + 1) - 143 x (102 - 1)
= 145 x 100 - 143 x 101 = 145 x 100 - 143 x (100 + 1)
= 100 x (145 - 143) - 143
= 200 - 143 = 57
B) 54 x 47 - 47 x 53 - 20 - 27
= 47 x (54 - 53) - (20 + 27)
= 47 x 1 - 47 = 0
bài 1 : tính nhanh
(145 x 99 + 145) - (143 x 102 - 143)
54 x 47 - 47 x 53 - 20 - 27
2 x 8 x 50 x 25 x 125
bài 7:tính nhanh
a (145 x 99+145)-(143 x 102-143) b,54 x 47 - 47 x 53 - 20 -27
c, 10000 - 47 x 72 - 47 x 28 d, 3457 - 27 x 48 - 48 x 73 + 6543
a) \(\left(145\times99+145\right)-\left(143\times102-143\right)\)
\(=\left[145\times\left(99+1\right)\right]-\left[143\times\left(102-1\right)\right]\)
\(=\left(145\times100\right)-\left(143\times101\right)\)
\(=14500-14443\)
\(=57\)
b) \(54\times47-47\times53-20-27\)
\(=47\times\left(54-53\right)-20-27\)
\(=47-20-27\)
\(=0\)
c) \(10000-47\times72-47\times28\)
\(=10000-47\times\left(72+28\right)\)
\(=10000-47\times100\)
\(=10000-4700\)
\(=5300\)
d) \(3457-27\times48-48\times73+6543\)
\(=\left(3457+6543\right)-48\times\left(27+73\right)\)
\(=10000-48\times100\)
\(=10000-4800\)
\(=5200\)
bài 4: Tính nhanh
(145 x 99 + 145 ) – ( 143 x 102 – 143 × 2 ) + 54 x 47 – 47 x 53 – 20 – 27
có ai làm cho em ạ
xong thì em tick cho
\(=145\cdot100-143\cdot100+47\left(54-53-1\right)\)
\(=2\cdot100\)
=200
Tính nhanh:
54 x 113 + 45 x 113 + 113
54 x 47 - 47 x 53 - 20 - 27
10000 - 47 x 72 - 47 x 28
(145 x 99 + 145) - (143 x 101 - 143)
1002 x 9 - 18
8 x 427 x 3 + 6 x 573 x 4
2008 x 867 + 2009 x 133
a/ = 113 x ( 54 + 45 + 1 ) = 113 x 100 = 11300
b/ = 47 x ( 54 - 53 ) - 20 - 27 = 47 - 20 - 27 = 0
c/ = 145 x ( 99 + 1 ) - 143 x ( 101 - 1 ) = 145 x 100 - 143 x 100 = 100 x ( 145 - 143 ) = 100 x 2 = 200
d/ = 1002 x 9 - 2 x 9 = 9 x ( 1002 - 2 ) = 9 x 1000 = 9000
e/ = 24 x 427 + 24 x 573 = 24 x ( 427 + 573 ) = 24 x 1000 = 24000
f/ Sửa đề bài là :
2008 x 867 + 2008 x 133 = 2008 x ( 867 + 133 ) = 2008 x 1000 = 2008000
4. Tỉnh nhanh:
a. 8 * 427 * 3 + 6 * 573 * 4
d. (137 * 99 + 137) - (17 * 101 - 17)
b. 54 * 47 - 47 * 53 - 20 - 27
c. 6 * 1235 * 20 - 5 * 235 * 24
e. (145 * 99 + 145) - (143 * 101 - 143)
g. (2003-123 8:4) x (36:6-6)
Bài 4 : Tính nhanh
a, 8 * 427 *3 + 6 * 573 * 4
b, ( 145 * 99 + 145 ) - ( 143 * 102 - 143 )
c, 54 * 47 - 47 * 53 - 20 - 20 - 27