Average
- A person bought some oranges worth ₹ 36 from each of the five markets at ₹ 1, ₹ 1.50, ₹ 1.80, ₹ 2 and ₹ 2.25 per orange, respectively. What is the average price of an orange ?
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Number of oranges bought by the person
= 36/1 + 36/1.50 + 36/1.80 + 36/2 + 36/2.25
= 36 + 24 + 20 + 18 + 16
= 114
Total expenditure = 36 x 5 = ₹ 180Correct Option: C
Number of oranges bought by the person
= 36/1 + 36/1.50 + 36/1.80 + 36/2 + 36/2.25
= 36 + 24 + 20 + 18 + 16
= 114
Total expenditure = 36 x 5 = ₹ 180
Thus, average price of each orange
= ₹ 180/114
= ₹ 1.58
- Average of a, b and c is 11; average of c, d and e is 17; average of e and f is 22 and average of e and c is 17. Find out the average of a, b, c, d, e and f ?
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According to the question,
a + b + c = 11 x 3 = 33 ......(i)
c + d + e = 17 x 3 = 51 ...........(ii)
e + f = 22 x 2 = 44 ........... (iii)
e + c = 17 x 2 = 34 ..........(iv)
From Eqs. (ii) and (iv), we get
34 + d = 51
or d = 17 ....(v)
Now, by adding Eqs. (i), (iii) and (v), we get
a + b + c + d + e + f = 33 + 44 + 17 = 94Correct Option: A
According to the question,
a + b + c = 11 x 3 = 33 ......(i)
c + d + e = 17 x 3 = 51 ...........(ii)
e + f = 22 x 2 = 44 ........... (iii)
e + c = 17 x 2 = 34 ..........(iv)
From Eqs. (ii) and (iv), we get
34 + d = 51
or d = 17 ....(v)
Now, by adding Eqs. (i), (iii) and (v), we get
a + b + c + d + e + f = 33 + 44 + 17 = 94
∴ Average of a, b, c, d, e and f = 94/6
= 47 / 3
= 152/3
- The average age of 54 girls in a class was calculated as 14 yr. It was later relized that the actual age of one of the girls in the class was 10.5 yr but it was calculated as 13 yr. What is the actual averge age (round off) of the the girls in the class ? (Find the approximate answer.)
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Total actual age of 54 girls = (54 x 14) - 13 + 10 .5
= 753.5 yrCorrect Option: D
Total actual age of 54 girls = (54 x 14) - 13 + 10 .5
= 753.5 yr
∴ Require average age = 753.5/54
= 13.95 yr
= 14 yr(approx).
- The average age of a man and his two twin sons born on the same day is 30 yr. The ratio of the ages of father and one son is 5 : 2, What is the father's age ?
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According to the question,
Average age of man and his twin sons = 30
∴ Total age = 30 x 3 = 90 yr.
According to the question,
Ratio of father and one son = 5 : 2
∴ Ratio of father and both the sons = 5 : 2 : 2
(As sons are born on the same day.)Correct Option: A
According to the question,
Average age of man and his twin sons = 30
∴ Total age = 30 x 3 = 90 yr.
According to the question,
Ratio of father and one son = 5 : 2
∴ Ratio of father and both the sons = 5 : 2 : 2
(As sons are born on the same day.)
∴ 5k + 2k + 2k = 90 or 9k = 90
∴ k = 10
∴ Age of father = 5 x 10 = 50 yr.
- The ratio of pens and pencil in a stationary shop is 3 : 2, respectively, The average number of pens and pencils is 180. What is the 30% of number of pencils in the shop ?
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The average number of pens and pencils = 180
∴ Totol number of pens and pencils = 180 x 2 = 360
∴ Total number of pencils in the shop = 360 x (2/5) = 144Correct Option: E
The average number of pens and pencils = 180
∴ Totol number of pens and pencils = 180 x 2 = 360
∴ Total number of pencils in the shop = 360 x (2/5) = 144
∴ 30% of 144 = (30/100) x 144 = 43.2 = 43
= 43 (approx)
