averages Model Questions & Answers, Practice Test for ssc cgl tier 2

Answer: (b)

Total age of 10 students

= 15 × 10 = 150 yrs

Total age of 15 students

= 15 × 16= 240 yrs

∴ Average of new students

= ${240 - 150}/5$ = 18 yrs.

Answer: (d)

For 150 coins to be of a value of Rs.150, using only 25 paise, 50 paise and Rs. 1 coins, we cannot have any coins lower than the value of Rs. 1.

Thus, the number of 50 paise coins would be 0. Option (d) is correct.

Answer: (b)

Let the third number be = x

∴ First number = 3x and

second number = ${3x}/2$

According to the question.

or, $3x + {3x}/2 + x = 3 × 121$

or, ${6x + 3x + 2x}/2$ = 3 × 121

or, ${11x}/2$ = 3 × 121

∴ $x = {3 × 121 × 2}/11$ = 66

∴ Third number = 66

Required difference

= 3x – x = 2x = 2 × 66 = 132

Answer: (b)

Let number of boys and girls in the class is 4x and 3x also Average height of girl is h

Now,

⇒ 7x × 4.6 = 4x × 4.8 + 3x × h

⇒ 32.2x = 19.2x + 3x × h

∴ h = $13/3$ = $4.\ov3$

Answer: (e)

Avg. = ${148 + 88 + 184 + 166 + 96 + 122}/6$

= 134