# Quantitative Aptitude: Average Questions Set 3

1. The average weight of a group of 54 girls was calculated as 58 kg .It was later discovered  that the weight of one of the girls was read as 70 kg ,whereas her actual weight was 65kg. What is the  actual average weight  of the group of 54 girls ?
A)  57.5
B)  58.5
C)  57.9
D) 55.8
E) 54.0

Option  C
Solution:
Actual weight of 54 girls  = 54 * 58 + 65 – 70 = 3127
Required actual average weight = 3127/ 54 = 57.9

2. The average weight of 50 stduents in a class was calculated  as 42 kg .It was  later  found that the weight of two students  in the class was wrongly calculated .The actual weight of one of the  boys in the class was  38kg ., but it was calculated as 40 kg ,and the weight of another boy in the class was  55kg , whereas it was calculated as 50 kg .What is the actual average weight of the  50 students in the class ?
A)  42.06
B)  45
C)   47.3
D)  58
E)   40.75
Option A
Solution:
Actual weight of all the students = 50 * 42 – 40 + 38 – 50 +55 = 2103
Actual average weight = 2103/50 = 42.06

3. In sunny ‘s opinion his weight is greater than 65 kg but less than 72 kg .His cousin does not agree with sunny and he thinks that sunny’s weight is greater than 60kg but less than 70 kg .His elder brother ‘s view is that his weight cannot be greater than 68 kg .If all of them are correct in their estimation ,what is the average of different probably weights of sunny ?
A)  70 kg
B) 65 kg
C)  62 kg
D) 77 kg

Option E
Solution:
sunny ‘s opinion  = 65 < W< 72
cousin’s opinion = 60 < W < 70
Elder brother’s opinion = W  (not greater than ) 68  or W (is less than equals to) 68

4. There are 5 consecutive odd numbers .If the difference between the square of the average of the  first two odd numbers and square of the average of the last two odd numbers is 492 ,what is the smallest odd number ?
A)  35
B) 40
C) 37
D) 34
E) 48

Option C
Solution:
Five consecutive odd numbers = x , x+2, x +4 , x+6  and x +8
Now ,
[(x+6+x+8) /2]2   – [(x+x+2)/2]2 = 492
=>x= 444/12 = 37
Smallest odd number = 37

5. A batsman played three matches in a tournament .The respective ratio between the scores of 1st and 2nd matches was 5 :4 and that between the scores of 2nd and 3rd  matches was 2 :1 .The difference  between the 1st and 3rd matches was 48 runs . What was the batsman’s average score in all the three matches ?
A)  42(1/2)
B)  58(2/3)
C) 49(4/7)
D)  52(1/3)
E)  48(1/8)

Option B
Solution:
Match 1 : Match 2 = 5 :4
Match 2 : Match 3 = 2 : 1 = 4 :2
Therefore ,
Match 1 :Match 2 :Match 3 = 5 :4 : 2
Now ,
5x – 2x = 48
=> x= 16
Total runs scored in three matches = 5x + 4x +2x =11x
= 11 * 16 = 176
Required average = (176/3) =58(2/3)

6. In a certain year ,the average monthly income of a person was Rs. 3400 . For the first 8 months  of the year ,his average monthly income was Rs. 3160 and for the last 5 months ,it was Rs. 4120 .His income in the 8th month of the year ?
A)  Rs. 3147
B)  Rs . 5080
C)  Rs. 10,254
D)  Rs. 8800
E)  Rs. 7425

Option B
Solution:
Income in the 8th month = (8*3160 + 5*4120  – 12 * 3400) = Rs. 5080

7. Out of three numbers , the first is twice  the second and is half  of the third .If the average of the three  numbers is  56 ,the three numbers in order are :
A)  45 , 78 ,54
B)  47, 75 , 62
C)   52 , 68 , 80
D) 48 , 24 , 96
E)  None of these

Option D
Solution:
Suppose the numbers are n1 ,n2 and n3 .
Then ,
n1 : n2: n3  = 2 : 1 : 4
And
n1 + n2 + n3  = 56 * 3 = 168
n1 = (2/7) * 168 = 48
n2 = (1/7) * 168 = 24
n3 = (4/7) * 168 = 96
8. An aeroplane covers the four sides of square field at speeds of 200 km/hr  , 400km/hr , 600km/hr  and 800 km/hr .Then the average speed of the aeroplane in the entire journey is ?
A)  384 km/hr
B)  400km/hr
C) 450km/hr
D) 575 km/hr
E)  686 km/hr

Option A
Solution:
Suppose the side of the square is 2400 km
[LCM of 200,400,600 and 800 is 2400 kms ] Now,
Average speed = Total distance / Total time = (2400 * 4) /[(2400/200) + (2400/400) +(2400/600)+(2400/800)] = 9600/25 = 384 km /hr

9. The average salary of the entire staff in a office is Rs. 130 per month . The average salary of officers is Rs. 540 and that of non – officers is Rs . 114 . If the number of officers is 16 ,then find the  number of non- officers  in the office .
A)  442
B) 571
C) 410
D) 550
E) None of these

Option  C
Solution:
Officers                  Non – officers
540                               114
130
(  130 – 114  )        :          ( 540 – 130    )
16                :                  410

10. In a coconut grove ,(x+2) trees yield  60 nuts per year per tree , x trees yield  120 nuts per year per tree  and (x-2) trees yield 180 nuts per year per tree .If the average yield per year per tree be 100 .Find the value of x ?
A)   8
B)  10
C)  4
D) 12
E)  16

Option  C
Solution:
[60(x+2) +120x + 180(x-2)]/[x+2+x+x-2] =100
=> x = 240/60 =4

## 32 Thoughts to “Quantitative Aptitude: Average Questions Set 3”

1. Jellyfish

9/10 ty az
Que 3
Sunny opinion=65….72
Cousin opinion.. 60….70
Elder brother opinion… Not more than 68
So we will get middle value 66&67
66+67/2=66.5 ans

1. cActi?

Here..we have only opinions of two persons. We can’t predict the age of an individual.
Dekho ..
Yahan pe Teen logo ka opinions diya hua h.. Teeno ke opinions ko dekhte hue..hame values uncertain mil rahe.

1. Jellyfish

Same question u will get rs agrwal book ans given 66.5 check it

1. cActi?

But u urself see…. Kya hume aisa koi number mil raha h jisse ki hum kisika age nikal sake.. If I’m assuming opinions of these three persons.

1. Jellyfish

Okk thx

2. cActi?

None of these..
In that Ques.

3. Jellyfish

Hmm aab correct hua que me probable puch hai so iss liye 66.5 aayega

4. Bhavana

bt yha different probably weights ka avg puchh ra….kisi certain weight ka ni..

5. Bhavana

correct me if i m geting it wrong..

6. cActi?

No dear u r not wrong.. Consider none of these in the option.

2. thinker

How ?

1. Jellyfish

Que me sabhi KO opinion correct manakar ham 66,67 value milti hai so probably average 66+67/2=66.5 aayega

1. thinker

Ok value to mujhe malum thi .ye Ni malum tha aese case me average nikalte h

2. thinker

Ek slah chahiye thi aapse.computer me thodi si halt khasta h.esliye net se note bna rhi hun kon kon se topic or notes bnane chahiye.Actully new technology wagarh k bare me jada knowledge Ni h.so plz tell me

1. Jellyfish

Computer me meri bhi halt bekar hai but AC site ke quiz Karo sab aur az isse kafi concept bhi clear ho jayega koi book ki jaruurat nahi hogi aur pm&ob st doge to question jaruur dekhna

2. thinker

Ok

2. _/_

ty
There are 5 consecutive odd numbers .If the difference between the square of the average of the first two odd numbers and square of the average of the last two odd numbers is 492 ,what is the smallest odd number ?
A) 35
B) 40
C) 37
D) 34
E) 48

Option C
any other way or shortrick?

1. cActi?

We have to find out the squares.. In order to get the value of X.

2. **Peaceful warrior**

Let odd no. r 1…3..5…7…9
{(7+9)/2}^2 – {(1+3)/2}^2=60
(492/60)×5=41
Mean= 5=41
1=?=37

1. thinker

Nice .mere ek question ko b short form me Kr do plz.A+B+C work ko x hour me krte h.A alone x+6 hour me krta h.B alone x+1 hour me krta h.C alone 2x hour me krta h.A work ko kitne hour me krega

1. **Peaceful warrior**

Ans??? 20/3
A+B+C :C= 2:1
A+B =C
{(1/x+6)+(1/x+1)}=1/2x
(2x+7)/(x^2+6+7x)=1/2x
3x(x+3)-2(x+3)=0
x# -3
So x= 2/3
A= 2/3 +6=20/3
B=2/3 +1=5/3
C=4/3
Now check method crct or not
20/3 , 5/3,4/3 LCM 20/3
A=1,B=4,C=5
1day work =10
20/3 ÷10=2/3=x satisfy

1. thinker

Nice thank you

3. Marry..

ty AZ

1. cActi?

171/442 ?

1. swati

1. Arun v Kumar

iam getting 25/102 could u pls explain

4. jaga

THANK U

5. Parag Chavda

i analyse all sets, all sets have difficulty level is below average, and ssc chsl level, please upload questions on bank po level, as possible as toughest level so that student gain more benefit as exam point of view!

6. EKTA

10/10