1 % x45 =
1/2 x45 +0,5x37+ 5/10x18
1/2 × 45 + 0,5 × 37 + 5/10 × 18
= 0,5 × 45 + 0,5 × 37 + 0,5 × 18
= 0,5 × (45 + 37 + 18)
= 0,5 × 100
= 50
đề bài
=1/2 x 45 + 1/2 x 37 + 1/2 x18
=1/2x(45+37+18)
=1/2 x 100
=100/2
=50
1. Tính bằng cách thuận tiện nhất:
a. 34,67 + 5,42 + 4, 58
b. 15,27 x 2 x 0,5
c. 45,28 x45 + 45,28 x 55
`a,`
`34,67+5,42+4,58`
`= 34,67+(5,42+4,58)=34,67+10=44,67`
`b,`
`15,27 \times 2 \times 0,5`
`= 15,27 \times (2 \times 0,5)`
`= 15,27 \times 1=15,27`
`c,`
`45,28 \times 45 + 45,28 \times 55`
`= 45,28 \times (45+55)`
`= 45,28 \times 100=4528`
a.
34,67 + 5,42 + 4,58
= (34,67 + 5,42) + 4,58= 40,09 + 4,58 = 44,67
b. 15,27 x 2 x 0.5
= (15,27 x 2) x 0.5 = 30,54 x 0,5 = 15,27
c. 45,28 x45 + 45,28 x 55
= 45,28 x (45 + 55)
= 45,28 x 100 = 4528
x ; 0,2 +x x45=550
(2³x9⁴+9³x45)(9²x10-9²)
`=(2^3xx9^4+9^3xx9xx5)(9^2xx10-9^2)`
`=(2^3xx9^4+9^4xx5)(9^2xx9)`
`=13.9^4. 9^3=13xx9^7.`
315x55 +315 x45 b) 678 x125 – 25 x678
a) 315 ✖55 + 315✖45 b) 678✖125-25✖678
= 315✖(55+45) =678✖(125-25)
=315 ✖ 100 =678✖100
=31500 =67800
315 x 55 + 315 x 45
= 315 x ( 55 + 45 )
= 315 x 100
= 31500
566-...-780-898-...x45=
(23 x 94+93 x45): (92x10-92)
mik cần gấp
\(=\dfrac{9^3\left(2^3\cdot9+45\right)}{9^2\cdot9}=8\cdot9+45=117\)
30,11 x45 -20,11x65+30,11x55-20,11x35
Tìm X
45 x X - 9 x X + X + 63 x X = 54000