Dell Average Questions

b = a + 2
c = b + 2 = a + 4
d = c + 2 = a + 6
e = d + 2 = a + 8
Therefore, Required average =
(a + a + 2 + a + 4 + a + 6 + a + 8)/5
= a + 4

If the average of remaining numbers be x,
then
20 × 15 = 5 × 12 + 15x
⇒ 300 = 60 + 15x
⇒ 15x = 300 – 60 = 240
=> x = 240/15 = 16

Let he has taken X wickets before the match.

And runs given with the average 12.4,
So total run given was,

= 12.4X
Runs given including this match,

12.4X +26 with the average of 12.

Now,
(12.4X+26)/(X+5) = 12
12.4X + 26 = 12X + 60
0.4X = 34
X = 85 wickets

if x is the average bill
16x = 15*80 + x+75
15 x = 1275
x= 85
16x = 1360

Total sale for 5 months = Rs. (6435 + 6927 +
6855 + 7230 + 6562) = Rs. 34009.
Required sale = Rs. [ (6500 x 6) - 34009 ]
= Rs. (39000 - 34009)
= Rs. 4991

Sum of the numbers =3×77=231

Let third number be x
Then, second number =2x
first number =4x

x+2x+4x=231
⇒x=33

First number =4x=132

Total weight of the 34 students
=34×45=1530

Total weight of the 34 students and the
teacher
=35×45.4=1589

Therefore, weight of the teacher
=1589−1530=59 kg

Let average age of 10 elephants =x
Then, total age of 10 elephants =10x

Let sum of the ages of the 2 tortoises =y

From the problem,
(10x−50−60+y)/10=x+8
x−5−6+y/10=x+8
−5−6+y/10=8
y/10=19
y=190

Average age of tortoises =190/2=95

Let number of boys =100x
number of girls =1500−100x

Passed boys ={100x)×80/100=80x
Passed girls =(1500−100x)70/100
=1050−70x
Total number of passed students =80x+1050−70x=1050+10x

(1050+10x)/1500=75/100
(1050+10x)/1500=3/4
1050+10x=1125
10x=75
100x=750

Number of boys appeared in the exam =750

Number of boys failed =750×(20/100)=150

Number of even numbers =(500−200)/2+1
=151

Sum =151/2(200+500)=52850

Average =1/2(200+500)=350

Average of 20 numbers = 0.

Sum of 20 numbers = (0 * 20) = 0.

It is quite possible that 19 of these numbers
may be positive and if their sum is a,
then 20th number is (- a).

Let the numbers be x, x + 1, x + 2, x + 3,
x + 4, x + 5 and x + 6,
Then (x + (x + 1) + (x + 2) + (x + 3) +
(x + 4) + (x + 5) + (x + 6)) / 7 = 20.
or 7x + 21 = 140 or 7x = 119 or x =17.
Latest number = x + 6 = 23.