Gọi số lớn là a; số nhỏ là b

Ta có: a - b = 33

           a = 3b + 3

\(\Rightarrow3b+3-b=33\)\(\Rightarrow2b=30\)\(\Rightarrow b=15\)\(\Rightarrow a=33+b=33+15=48\)

Vậy a = 48; b = 15

số 48 và 15.

Cj Mai nhận đc số tiền là:

   (37.50 000)+(8.40 000)=2 170 000( đồng )

Số tiền chị Lan nhận được là: 50.45–40.5=2050(ngàn)

hok tốt

49³ / 7⁹ = 7⁶ / 7⁹ = 1/7³

4² / 2⁷ = 2⁴ / 2⁷ = 1/2³

49³ : 7⁹

= ( 7 )^{2 . 3} : 7⁹

= 7⁶ : 7⁹

= 7^{6 - 9}

= 7 ^{( - 3 )}

\(G=\left(864.48-432.96\right):\left(864.48.432\right)\)

\(\Rightarrow G=\left(432.2.48-432.96\right):\left(864.48.432\right)\)

\(\Rightarrow G=\left[432.\left(2.48-96\right)\right]:\left(864.48.432\right)\)

\(\Rightarrow G=\left(432.0\right):\left(864.48.432\right)\) \(\Rightarrow G=0:\left(864.48.432\right)\) \(\Rightarrow G=0\)

a) \(\widehat{zÕx}+\widehat{zOy}=\widehat{xOy}\)

\(\Leftrightarrow\widehat{zOx}=\widehat{xOy}-\widehat{yOz}=180^o-60^o=120^o\)

b) \(\widehat{zOM}+\widehat{zON}=\frac{1}{2}\widehat{zOx}+\frac{1}{2}\widehat{zOy}=\frac{1}{2}\widehat{xOy}=\frac{1}{2}.180^o=90^o\)

Do đó \(\widehat{zOM}\)và \(\widehat{zON}\)phụ nhau. 

      \(\frac{3}{1}+\frac{3}{3}+\frac{3}{6}+\frac{3}{10}+...+\frac{3}{x.\left(x+1\right):2}=\frac{2015}{336}\)

\(\Leftrightarrow\frac{6}{2}+\frac{6}{6}+\frac{6}{12}+\frac{6}{20}+...+\frac{6}{x\left(x+1\right)}=\frac{2015}{2016}\)

\(\Leftrightarrow6\left(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{x\left(x+1\right)}\right)=\frac{2015}{336}\)

\(\Leftrightarrow\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+...+\frac{1}{x\left(x+1\right)}=\frac{2015}{2016}\)

\(\Leftrightarrow1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+...+\frac{1}{x}-\frac{1}{x+1}=\frac{2015}{2016}\)

\(\Leftrightarrow1-\frac{1}{x+1}=\frac{2015}{2016}\)

\(\Leftrightarrow\frac{1}{x+1}=\frac{1}{2016}\)

\(\Leftrightarrow x+1=2016\)

\(\Leftrightarrow x=2015\)

     Vậy \(x=2015\).

K = (168 x 168 - 168 x 58) : 110 + [(456 x 11 + 912) x 37] : (13 x 74)

\(\Rightarrow K=\left[168.\left(168-58\right)\right]:110+\left[456\left(11+2\right).37\right]:\left(13.74\right)\)

\(\Rightarrow K=168.110:110+\left(456.13.37\right):\left(13.74\right)\)

\(\Rightarrow K=168+\left(228.13.74\right):\left(13.74\right)\)

\(\Rightarrow K=168+228.\left(13:13\right).\left(74:74\right)\)

\(\Rightarrow K=168+228=396\)