tinh 437269 - 3 nhan 102951
tinh nhanh
1/10 nhan 2/9 nhan 3/8 nhan 4/7 nhan 5/6 nhan 6/5 nhan 7/4 nhan 8/3 nhan 9/ 2
1/10x(2/9x9/2)x(3/8x8/3)x(5/6x6/5)=1/10x1x1x1=1/10
Tinh nhanh ;3,9 nhan 78,24 + 1,3 nhan 21,76 nhan 3
\(=3,9x78,24+3,9x21,76=3,9x\left(78,24+21,76\right)=3,9x100=390\)
234 nhan 25 nhan 3 nhan 4 tinh bang cach thuan tien nhat
Ta có : 234.25.3.4=(234.3).(25.4)=702.100=70200
234*25*3*4
=(234*3)*(25*4)
=702*100
=70200
tinh bang cach thuan tien
0,27 nhan 131 nhan 1,35 nhan 4557 chia 0,5 cong 3 nhan 5312 nhan 0,9
1/5 nhan 2/6 nhan 3/7 nhan 4/8 tinh nhanh nha
\(=\frac{1}{5}\times\frac{1}{3}\times\frac{3}{7}\times\frac{1}{2}\)
\(=\left(\frac{1}{5}\times\frac{1}{2}\right)\times\left(\frac{1}{3}\times\frac{3}{7}\right)\)
\(=\frac{1}{10}\times\frac{1}{7}\)
\(=\frac{1}{70}\)
Tinh
1/3 nhan 3/5 nhan 5/9
\(\frac{1}{3}\)x \(\frac{3}{5}\)x \(\frac{5}{9}\)= \(\frac{15}{135}\)= \(\frac{1}{9}\)
\(\frac{1}{3}.\frac{3}{5}.\frac{5}{9}=\frac{1}{9}\)
\(\frac{1}{3}\cdot\frac{3}{5}\cdot\frac{5}{9}=\frac{1}{9}\)
Tinh gia tri cua bieu thuc :
3/4 nhan 8/9 nhan 15/16 nhan ...nhan 99/100 =
ko được phép đăng ak
tinh nhanh 125 nhan 3 cong 125 nhan 2 cong 125 nhan 3 cong 125 cong 1
125 x 3 + 125 x 2 + 125 x 3 + 125 x 1
= 125 x ( 3 + 2 + 3 + 1 )
= 125 x ( 5 + 3 + 1 )
= 125 x ( 8 + 1 )
= 125 x 9
= 1125
tinh bang cach thuan tien
0,27 nhan 131 nhan 10 cong 1,35 nhan 4557 chia 0,5 cong 3 nhan 5312 nhan 0,9