tính hợp lý
\(\frac{41.61+34.41}{3+7+11+...+79}\)
\(\frac{1997.1996-1}{1995.1997+1996}\)
\(\frac{254.399-145}{254+399.253}\)
Tính hợp lý
\(\frac{254.399-145}{254+399.253}\)
đặt biểu thức trên là A
xét A- 1 = \(\frac{254.399-253.399-145-254}{254+399.253}=\frac{399-399}{254+399.253}=0;\) => A= 1
\(\frac{254.399-145}{254+399.253}\)
\(=\)\(\frac{\left(253+1\right).399-145}{254+399.253}\)
\(=\)\(\frac{253.399+399-145}{254+399.253}\)
\(=\)\(\frac{253.399+254}{254+399.253}\)
\(=\)\(1\)
Tính hợp lý
\(\frac{1997.1996-1}{1995.1997+1996}\)
\(\frac{1997\times1996-1}{1995\times1997+1996}\)
\(=\frac{1997\times\left(1995+1\right)-1}{1995\times1997+1996}\)
\(=\frac{1997\times1995+1997-1}{1995\times1997+1996}\)
\(=\frac{1997\times1995+1996}{1995\times1997+1996}=1\)
Bài 1 : Tính
a, \(\frac{1995}{1996}\). \(\frac{19961996}{19311931}\).\(\frac{193119311931}{199519951995}\)= ?
b,\(\frac{1313}{2121}\).\(\frac{165165}{143143}\).\(\frac{424242}{151515}\)=?
c,\(\frac{1997.1996-1}{1995.1997+1996}\)= ?
d,\(\frac{1997.1996-1}{1995.1997+1996}\)=?
Mk cần gấp lắm giải giúp mk nha ♣♣♣
\(a,\frac{1995}{1996}.\frac{19961996}{19311931}.\frac{193119311931}{199519951995}\) \(c,\frac{1997.1996-1}{1995.1997+1996}\)
\(=\frac{1995}{1996}.\frac{1996}{1931}.\frac{1931}{1995}\) \(=\frac{1997.\left(1995+1\right)-1}{1995.1997+1996}\)
\(=\frac{1995.1996.1931}{1996.1931.1995}\) \(=\frac{1997.1995+1997-1}{1997.1995+1996}\)
\(=1\) \(=\frac{1997.1995+1996}{1995.1997+1996}\)
\(=1\)
Ý (a) giống ý (b)
Ý (c) giống ý (d)
1.Tính
x-6=11
\(\dfrac{254.399-145}{254+399.253}\)
x-6=11
<=>x=11+6
=>x=17
TICK cho mình với các bạn
\(a,x-6=11\)
\(x=11+6\)
\(\Rightarrow x=17\)
\(b,\dfrac{254.399-145}{254+399.253}=\dfrac{\left(253+1\right).399-145}{254+399.253}\)
\(=\dfrac{253.399+399-145}{254+399.253}\)
\(=\dfrac{253.399+254}{254+399.253}\)
\(=1\)
\(\dfrac{254.399-145}{254+399.253}\)
\(\dfrac{254.399-145}{254+399.253}=\dfrac{101346-145}{254+100947}=1\)
TICK cho mình với nhé các bạn
\(\dfrac{254.399-145}{254+399.253}\)=\(\dfrac{101346-145}{254+100947}\)=\(\dfrac{101201}{101201}\)=1
\(\dfrac{254.399+145}{254+399.253}\)
\(=\dfrac{\left(253+1\right).399-145}{254+399.253}\)
\(=\dfrac{253.399+399-145}{254+399.253}\)
=\(\dfrac{399.253+254}{254+399.253}=1\)
1) : Tính bằng cách hợp lý .
a) A = \(\frac{41.66+34.41}{3+7+11+...+79}\)
b) B = \(\frac{1+2+3+...+200}{6+8+10+...+34}\)
c) C = \(\frac{1..5.6+2.10.12+4.20.24+9.45.54}{1.3.5+2.6.10+4.12.20+9.27.45}\)
Tính hợp lí: \(A=\frac{41.66+34.41}{3+7+11+...+79}\)
\(A=\frac{41.66+34.41}{3+7+11+...+79}\)
\(A=\frac{41.\left(66+34\right)}{3+7+11+...+79}\)
\(A=\frac{41.100}{820}\)
\(A=\frac{4100}{820}\)
\(A=5\)
Vậy \(A=5\)
mình viết phân số hơi nhỏ 1 tí
help me, please
1, tính = cách hợp lý\
c, C = \(\frac{1.5.6+2.10.12+4.20.24+9.45.54}{1.3.5+2.6.10+4.12.20+9.27+45}\)
b, B= \(\frac{1+2+3+.....+200}{6+8+10+....+34}\)
a, A = \(\frac{44.66+34.41}{3+7+11+......+79}\)