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The sum of the marks is : 17 + 13 + 5 + 10 + 14 + 9 + 12 + 16 = 96

The average of the marks is : 96 : 8 = 12

After removing 2 marks without changing the average,the sum of the marks is : 12 x (8 - 2) = 72

This sum decreased by : 96 - 72 = 24

In the given choices,there's only 10 + 14 = 24.Hence,the answer is E

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Draw AE // BC.

The quadrilateral ABCE has AB // CE ; AE // BC,so it's a parallelogram

$\Rightarrow A B = C E; \hat{E_{1}} = \hat{B} = 125^{0} \Rightarrow \hat{E_{2}} = 180^{0} - \hat{E_{1}} = 55^{0}$

$\hat{E_{1}}$ is the exterior angle of $Δ A D E$ $\Rightarrow \hat{A_{1}} + \hat{D} = \hat{E_{1}}$

$\Rightarrow \hat{A_{1}} = 125^{0} - 70^{0} = 55^{0}$

$Δ A D E$ has $\hat{A_{1}} = \hat{E_{2}} = 55^{0}$ ,so $Δ A D E$ isosceles at D

$\Rightarrow A D = D E \Rightarrow C D = C E + D E = A B + A D$

P/S : The question must be changed into $\hat{D} = 70^{0}$ or $\hat{B} = {127.5}^{0}$

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What did you try?

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let b an r be the price of a loaf of bread and a roll respectively.

Now we have:

_b+6r = 1.8

_2b+4r = 2.4

=>

_b+6r=1.8

_3b+6r=3.6

=>2b=1.8 and b=0.9

Hence, one loaf of bread costs 0.90

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123456789+987654321=1111111110

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24X8Y divisible 5 =. Y = 0 or 5 but 24X8Y divisible => Y = 0

24X80 divisible 9 => (2+4+X+8+0) divisible 9 => (14+X) divisible 9 => X =4

=> The sum of X and Y is:

4+0=4

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The largest number and the smallest number in Marry's list are 800 and 107 respectively.

Their sum ' s : 107+800 = 907