Tính nhanh
24*3 + 24* 5 + 24*2
Tính nhanh
24 x 5 + 24 x 3 + 24 x 2
* 24 x 5 + 24 x 3 + 24 x 2
= 24 x (5 + 3 + 2)
= 24 x 10
= 240
240 NHÉ -...-
DỄ THẾ CŨNG HỎI
Tính nhanh
a) (24 × 6 + 4 × 24) : ( 49 - 24 × 2)
b) 51 × 2 × 3 × 5
Tính nhanh
a) (24 x 6 + 4 x 24) : ( 49 - 24 x 2)
b) 51 x 2 x 3 x 5
Tính nhanh 24/3×9 + 24/9×5+24/15×21+............+24/57×63
Sửa đề:
24/(3×9) + 24/(9×15) + 24/(15×21) + ... + 24/(57×63)
= 24 × 1/6 × (1/3 - 1/9 + 1/9 - 1/15 + 1/15 - 1/21 + ... + 1/57 - 1/63)
= 4 × (1/3 - 1/63)
= 4 × 20/63
= 80/63
Chỗ \(\dfrac{24}{9\times5}\) là sao em nhỉ? đã đúng đề chưa thế em
Tính nhanh
2×169×12-3×68×8-24
2×56×24-3×36×16+4×12×95-6×3×8×5
\(2\times169\times12-3\times68\times8-24\)
\(=24\times169-24\times68-24\)
\(=24\times\left(169-68-1\right)\)
\(=24\times100=2400\)
Tính nhanh :
a, 24 . 64 + 36 . 24 - 100 . 24
b, 5 . 4² - 16 : 2²
\(a.24.64+36.24-100.24\)
\(=24.\left(64+36-100\right)\)
\(=24.0\)
\(=0\)
\(b.5.4^2-16:2^2\)
\(=5.16-16:4\)
\(=80-4\)
\(=76\)
Hok tốt
a, 24.64+36.24-100.24
=24.(64+36-1000
=24.0
=0
b, 5.4^2-16:2^2
=80-4
=76
a, 24 . 64 + 36 . 24 - 100 . 24
= 24 . ( 64 + 36 ) - 100
= 24 . ( 100 - 100 )
= 24 . 0
= 0
Tính nhanh:
1/9×10 + 2/10×12 + 3/12×15 + 4/15×19 + 5/15×24 + 6/24 ×30
\(\frac{1}{9\cdot10}+\frac{2}{10\cdot12}+\frac{3}{12\cdot15}+\frac{4}{15\cdot19}+\frac{5}{19\cdot24}+\frac{6}{24\cdot30}
\)
\(=\frac{1}{9}-\frac{1}{10}+\frac{1}{10}-\frac{1}{12}+\frac{1}{12}-\frac{1}{15}+\frac{1}{15}-\frac{1}{19}+\frac{1}{19}-\frac{1}{24}+\frac{1}{24}-\frac{1}{30}\)
\(=\frac{1}{9}-\frac{1}{30}\)
\(=\frac{10}{90}-\frac{3}{90}\)
\(=\frac{7}{90}\)
TÍNH NHANH
1) 24.( 16-5) -16.(24-5)
2)31.(-18)+31.(-18)-31
3) 13.(23+22) - 3.(17+28)
4) 19.25+9.95+19.30
Tính nhanh
24 . ( 16 - 5 ) - 16 . ( 24 - 5 )
24 . ( 16 - 5 ) - 16 . ( 24 - 5 )
= 24 . 16 - 24 . 5 - 16 . 24 - 16 . 5
= -24 . 5 - 16 . 5
= -40 . 5
= -200
24 . ( 16 - 5 ) - 16 . ( 24 - 5 )
= 24 . 16 - 24 . 5 - 16 . 24 - 16 . 5
= 24 . ( 16 - 5 ) - 16 . ( 24 - 5 )
= 24 . 11 - 16 . 21
= ( 24 - 16 ) . ( 11 - 21 )
= 8 . - 10
= - 80
24 . ( 16 - 5 ) - 16 . ( 24 - 5 )
= 24 . 16 - 24 . 5 - 16 . 24 + 16 .5
= 24 . ( 16 - 16) - 5 ( 24 -16 )
= 24 . 0 - 5 . 8
= 0 - 40
= - 40