1 tìm x
25/3-x=5/6
2 tính
3/7*5/4+5/14
Bài 1: Tính
3/5 + 4/3 x 5/6 2 - 7/6 + 1/3 7/6 x 3 - 3/5
giúp mình với, trả lời mình tick cho
\(\dfrac{3}{5}+\dfrac{4}{3}\times\dfrac{5}{6}=\dfrac{3}{5}+\dfrac{10}{9}=\dfrac{27}{45}+\dfrac{50}{45}=\dfrac{77}{45}\)
\(2-\dfrac{7}{6}+\dfrac{1}{3}=\dfrac{12}{6}-\dfrac{7}{6}+\dfrac{2}{6}=\dfrac{7}{6}\)
\(\dfrac{7}{6}\times3-\dfrac{3}{5}=\dfrac{7}{2}-\dfrac{3}{5}=\dfrac{35}{10}-\dfrac{6}{10}=\dfrac{29}{10}\)
1.tính bằng hai cách
(2/3-4/5)x25 3/4x2/503/4x2/7
2.tìm x
x:2/5=2/3 x:2/3=4/9
1.tính bằng hai cách
(2/3-4/5)x25 3/4x2/503/4x2/7
2.tìm x
x:2/5=2/3 x:2/3=4/9
Tính
a. 15 / 9 :3/4 :7/5
b. 23/7 x25/2 -23 /7 x ( 5 +1/2 )
a) \(\frac{15}{9}:\frac{3}{4}:\frac{7}{5}=\frac{15}{9}.\frac{4}{3}.\frac{5}{7}=\frac{300}{189}=\frac{100}{63}\)
b ) \(\frac{23}{7}.\frac{25}{2}-\frac{23}{7}.\left(5+\frac{1}{2}\right)=\frac{23}{7}.\left(\frac{25}{2}-\frac{11}{2}\right)=\frac{23}{7}.7=23\)
a)\(\frac{15}{9}x\frac{4}{3}x\frac{5}{7}=\frac{15x4x5}{9x3x7}=\frac{100}{63}\)
b)23
tính nhanh : a, 9 x 12 x25 b, 12 x 125 x 54 c, 8 x 9 x 14 + 6 x 7 x 12 + 19 x 4 x 18 d, 425 x 7 x 4 - 170 x 60 e, 1 + 5 + 9 + 13 + ... + 57 + 61 + 65
a,9.3.4.25
= 27.100
= 2700
b, 12.125.54
= 3.4.125.54
= 125.4.3.54
= 500.162
= 81000
c: \(=72\cdot14+72\cdot7+72\cdot19=72\cdot40=2880\)
d: \(=1700\cdot7-1700\cdot6=1700\)
e: Số số hạng là (65-1)/4+1=17(số)
Tổng là: \(\dfrac{65+1}{2}\cdot17=33\cdot17=561\)
rút gọn phân số
914x255x87/812x6153x253
\(\frac{9^{14}.25^5.8^7}{8^{12}.615^3.25^3}\)
\(=\frac{\left(3^3\right)^{14}.\left(5^2\right)^5.8^7}{8^{12}.\left(3.5.41\right)^3.\left(5^2\right)^3}\)
\(=\frac{3^{42}.5^{10}.8^7}{8^{12}.3^3.5^7.41^3}\)
\(=\frac{3^{39}.5^3}{8^5.41^3}\)
Tìm x:
a.62/7*x=29/9:3/56
b.4/5:x=1/5-1/7
c.5x+1/2=2/3
d.1/7-3/5x=3/5
tính
3 x 5/11
16/64 x 15/24
1/6 : 1/5
7/12 : 1/4
\(3\times\dfrac{5}{11}=\dfrac{15}{11}\)
\(\dfrac{16}{64}\times\dfrac{15}{24}=\dfrac{5}{32}\)
\(\dfrac{1}{6}:\dfrac{1}{5}=\dfrac{5}{6}\)
\(\dfrac{7}{12}:\dfrac{1}{4}=\dfrac{7}{3}\)
tính
3/4x5/7 5/8x4/15 7/12x4/9 1/6x3/5 12/21x23/8 13/4x5/39 7/42x13/21 3/16x4/15
ai e tick cho
\(\dfrac{3}{4}\times\dfrac{5}{7}=\dfrac{15}{28};\dfrac{5}{8}\times\dfrac{4}{15}=\dfrac{20}{120}=\dfrac{1}{6};\dfrac{7}{12}\times\dfrac{4}{9}=\dfrac{28}{108}=\dfrac{7}{27};\)
\(\dfrac{1}{6}\times\dfrac{3}{5}=\dfrac{3}{30}=\dfrac{1}{10};\dfrac{12}{21}\times\dfrac{23}{8}=\dfrac{276}{168}=\dfrac{23}{14};\dfrac{13}{4}\times\dfrac{5}{39}=\dfrac{65}{156}=\dfrac{5}{12}\)
\(\dfrac{7}{42}\times\dfrac{13}{21}=\dfrac{91}{882}=\dfrac{13}{126};\dfrac{3}{16}\times\dfrac{4}{15}=\dfrac{12}{240}=\dfrac{1}{20}\)
tính
3/7+(-18)/5+18/7+23/5
\(\dfrac{3}{7}+\dfrac{\left(-18\right)}{5}+\dfrac{18}{7}+\dfrac{23}{5}\)
\(=\left(\dfrac{3}{7}+\dfrac{18}{7}\right)+\left(\dfrac{-18}{5}+\dfrac{23}{5}\right)\)
\(=3+1\)
\(=4\)