Bài 3: Rút gọn các phân số sau:
a) \(\dfrac{10.11+50.55+70.77}{11.12+55.60+77.84}\)
b) \(\dfrac{2^{19}.27^3+15.4^9.9^4}{6^9.2^{10}+12^{10}}\)
(Tớ cần lời giải tính nhanh và hợp lý ạ,giúp tớ vớii)
Rút gọn phân số:
\(A=\frac{10.11+50.55+70.77}{11.12+55.60+77.84}\)
=110+110.25+110.49/132+132.25+132.49
=110(1+25+49)/132(1+25+49)
=110/132=5/6
Ai giúp mk vs tìm x biet a,7/x=x/28 b, 10+x/17+x=3/4 giúp mk vs ai nhanh nhất mk sẽ tick 2. Rut gọn a,10.11+50.55+70.77/11.12+55.60+77.84 giúp mk vssssss
\(a,\frac{7}{x}=\frac{x}{28}=>x\cdot x=28\cdot7=>x^2=196=>x^2=14^2\)\(=>x=14\)
\(b,\frac{10+x}{x+17}=\frac{3}{4}=>\left(10+x\right)\cdot4=\left(x+17\right)\cdot3=>40+x4=x3+51\)\(=>x4-x3=51-40=>x=11\)
Tìm x
\(\dfrac{10+x}{17+x}=\dfrac{10.11+50.55+70.77}{11.12+55.60+77.84}\left(x\ne-17\right)\)
\(\dfrac{10+x}{17+x}=\dfrac{10\cdot11+50\cdot55+70\cdot77}{11\cdot12+55\cdot66+77\cdot84}\)
\(\Leftrightarrow\dfrac{10+x}{17+x}=\dfrac{10\cdot11+5\cdot10\cdot111+7\cdot10\cdot11}{11\cdot12+5\cdot11\cdot12+7\cdot11\cdot12}\)
\(\Leftrightarrow\dfrac{10+x}{17+x}=\dfrac{10\cdot11\left(1+5+7\right)}{11\cdot12\left(1+5+7\right)}\)
\(\Leftrightarrow\dfrac{10+x}{17+x}=\dfrac{5}{6}\)
\(\Leftrightarrow6\left(10+x\right)=5\left(17+x\right)\)
\(\Leftrightarrow60+6x=85+5x\)
\(\Leftrightarrow6x-5x=85-60\)
\(\Leftrightarrow x=25\) (TM x\(\ne17\))
Vậy ...................................
Giải giúp mik bài toan bày nhé:
Rút gọn phân số:
a)\(\frac{10.11+50.55+70.77}{11.12+55.60+77.84}\)
b)\(\frac{1.3.5...99}{51.52.53...100}\)
10.11+50.55+70.77/11.12+55.60+77.84 tính
Rút gọn:
a) \(\frac{10.11+50.55+70.77}{11.12+55.60+77.84}\)
b) \(\frac{1.3.5.7.....49}{26.27.28.29.....50}\)
\(\frac{10.11+50.55+70.77}{11.12+55.60+77.84}=\frac{10.11.\left(1+5.5+7.7\right)}{11.12.\left(1+5.5+7.7\right)}=\frac{10}{12}=\frac{5}{6}\)
Rút gọn
a) \(\frac{10.11+50.55+70.77}{11.12+55.60+77.84}\)
b) \(\frac{1.3.5.7...49
}{26.27.28...50}\)
Giúp mik với nha
Rút Gọn : \(\frac{10.11+55.60+70.77}{11.12+55.60+77.84}\)
\(\frac{10.11+55.60+70.77}{11.12+55.60+77.84}=\frac{10.11+5.11.6.10+7.10.7.11}{11.12+5.11.5.12+7.11.7.12}=\frac{10.11+30.10.11+49.10.11}{11.12+25.11.12+49.11.12}=\frac{10.11\left(1+30+49\right)}{11.12\left(1+25+49\right)}=\frac{5.80}{6.75}=\frac{8}{9}\)
\(\frac{2^{19}.27^3+15.4^9.9^4}{6^9.2^{10}+12^{10}}\) rút gọn phân số
\(=\dfrac{2^{19}\cdot3^9+2^{18}\cdot3^9\cdot5}{2^{19}\cdot3^9+2^{20}\cdot3^{10}}=\dfrac{2^{18}\cdot3^9\cdot\left(2+5\right)}{2^{19}\cdot3^9\cdot7}=\dfrac{1}{2}\)