Dear Readers, Important Average Problems for upcoming competitive Exams with Solutions. Average is an important topic from banking exam point of view. You could solve Average problems easily if you understand the basic concepts. Aspirants preparing for SBI Clerk, SBI PO, IBPS Clerk, IBPS PO, Insurance, RBI and other competitive examination can make of use these average problems. We have included some important average problems that are repeatedly asking in competitive exams. Practice lot of questions to become an expert in solving average problems and learn to use shortcuts.
Average Problems – Set 3
1).Average marks obtained in History by 45 students in ‘A’ divisions are 75 and the average marks obtained by 40 students in ‘B’ division are 78. What are the overall average marks obtained in History by the students in both the divisions (rounded off to two digits after decimal) ?
a) 76.81
b) 77.11
c) 77.41
d) 76.41
e) None of these
2).If the average marks of three batches of 55, 60 and 45 students respectively are 50, 55 and 60, then the average marks of all the students is
a) 54.68
b) 53.33
c) 55
d) 45
e) None of these
3).The average age of Jai’s family consisting of 4 members, 4 years ago, was 28 years. 2 years ago, a baby was born in the family. The average age of the family 2 years from now would be :
a) 26 years
b) 24 years
c) 28 years
d) 31 years
e) None of these
4).The average age of a man and his son is 48 years. The ratio of their age is 11 : 5 respectively. What will be the ratio of their age after 6 years?
a) 6 : 5
b) 5 : 3
c) 4 : 3
d) 2 : 1
e) 6 : 1
5).Veeru goes from A to B at 60 kmph and returns to A at speed of 50 kmph. Find the average speed of Veeru for the entire journey if the distance AB = 120 km.
a) 54.64 kmph
b) 54.54 kmph
c) 55 kmph
d) 65 kmph
e) None of these
6).Sambha travelled (1 / 3)rd of distance from Delhi to Jaipur at speed of 80 kmph, next (1 / 3)rd at speed of 90 kmph and the last (1 / 3)rd distance at speed of 100 kmph, the average speed of Sambha for the entire journey is
a) 90 kmph
b) 89.25 kmph
c) 90.16 kmph
d) 70.23 kmph
e) None of these
7).The average salary of Shilpa, Bipasha and Rani is Rs. 35000 per month. Also the average salary of Kajol and Raveena is Rs. 38000 per month. What is the average salary per month of all the five taken together?
a) Rs. 36, 200
b) Rs. 37, 400
c) Rs. 34, 700
d) Rs. 39, 200
e) Rs. 31, 800
8).The average daily wages of Mayawati from Monday to Friday is Rs. 450. If she earns Rs. 300 on Monday and Rs. 400 on Saturday, then find the average daily wages from Tuesday to Saturday.
a) Rs. 420
b) Rs. 465
c) Rs. 410
d) Rs. 470
e) Rs. 490
9).The average weight of 8 persons increases by 2.5 kg when a new person comes in place of one of them weighing 65 kg. What might be the weight of the new person ?
a) 65 kg
b) 85 kg
c) 76.5 kg
d) Data inadequate
e) None of these
10).The average age of five officers in a department is 32 years. If the age of their supervisor is added, the average age increased by 1. What is the supervisor’s age?
a) 32 years
b) 48 years
c) 38 years
d) 42 years
e) None of these
Answers:
1). d) 2). a) 3). c) 4). d) 5). b) 6). b) 7). a) 8). d) 9). b) 10). c)
Solution:
1).Required average marks = (45 × 75 + 40 × 78) / (45 + 40)
= (3375 + 3120) / 85
= 6495 / 85 = 76.41
Answer: d)
2).The required average marks = (50 × 50 + 60 × 55 + 45 × 60) / (55 + 60 + 45)
= (2750 + 3300 + 2700) / 160 = 8750 / 160 = 54.68
Answer: a)
3).4 years ago, total age of 4 members = 4 × 28 = 112 years
= Total Age of the family just before baby is born = 112 + 4 × 2 = 120 years
Total Present age of the family = 120 + 5 × 2 = 130
2 years hence the total age of the family = 130 + (5 × 2) = 140
Average age of the family two years hence = 140 / 5 = 28 years
Answer: c)
4).Sum of the age of man& son = 48 × 2 = 96
Given Ratio = 11 : 5 (i.e) age of man = (11 / 16) × 96 = 66 years&
That of son = 6 × 5 = 30 years
Ratio of their age 6 years hence would be (66 + 6) : (30 + 6) = 72 : 36 = 2 : 1
Answer: d)
5).Average Speed = (2xy) / (x + y) [Since distance travelled is same)
= (2 × 60 × 50) / (60 + 50) = 6000 / 110 = 54.54 kmph
Answer: b)
6).Since distance travelled at different speeds is same, we can use the shortcut
Average Speed = (3xyz) / (xy + yz + zx)
Answer: b)
7).Average Salary of all 5 = (35000 × 3 + 38000 × 2) / 5
=(105000 + 76000) / 5 = Rs. 36, 200
Answer: a)
8).Total wages from Monday to Friday = 450 × 5 = 2250
Total wages from Tuesday to Saturday = 2250 – 300 + 400 = 2350
Average from Tuesday to Saturday = 2350 / 5 = Rs. 470
Answer: d)
9).Since, the average weight increases by 2.5 kg, hence sum of the weight would increases by 2.5 × 8 = 20 kg
So, weight of new person should be 20 kg more than the one who is replaced
Weight of new person = 65 + 20 = 85 kg
Answer: b)
10).The new average is increased by 1 year, hence sum of the age would have increased by 6 years.
Age of supervisor = 32 + 6 = 38 years
Answer: c)