Average MCQs

Number of rows $=sqrt{5625} = 75$

Seventh observation $= 7 times 11 - 6 times 12 = 5$

$15 + text{ Rs. } 70 - (5 times text{ Rs. } 60 + 9 times text{ Rs. } 80 ) = text{ Rs. } 30$

The required number of girls $= frac{9 times 270 times 3}{135} = 54$

Given

$frac{a + b + c + .... + j}{10} = 7$

$Rightarrow a + b + c + .... + j = 70$

After multiplying by 12 in each term average

$= frac{70 times 12}{10} = 84$

The average weight of 100 girls = $frac{text{total weight}}{100}$

$=frac{150 times 60 - 50 times 70}{100}$

=55

Average of temperature from Monday to Wednesday = 36°C.
Total of temperature Monday to Wednesday = 36 $times$ 3 = 108°C
Average temperature Monday to Thursday = 37°C
Total of temperature Monday to Thursday = 37 $times$ 4 = 148°C
$therefore$ Temperature of Thursday = 148 — 108 = 40°C

Let the total score of 7 other person in the team $= 7x$,
Given if best shooter had scored 92 points then average $=frac{7x + 92}{8} = 84$
$begin{aligned} Rightarrow 7x &= 672 - 92 Rightarrow 7x &= 580 end{aligned}$
If the best shooter scored 85 points, then points scored by entire team
$begin{aligned} &= 7x + 85 &=580 + 85 =665 end{aligned}$

Let the four consecutive odd natural numbers are $x, x+2, x+4$ and $x+6$

$therefore$Sum of the four no. = 26 $times$ 4

$begin{aligned} x+x+2+x+4+x+6 &= 104 4x + 12 &= 104 4x &= 104 - 12 x &= frac{92}{4} x &= 23 end{aligned}$

$therefore$ The largest no. is = 23 + 6 = 29

The total of 5 numbers $= 8 times 5 = 40$

Therefore the total of last 3 numbers $= 3 times 6 =18$

and the total of first two numbers $= 40 - 18 = 22$

And, average of first two numbers $= frac{22}{2} = 11$