Question

The sum of four numbers is 100. The average of first second and fourth is 24. The difference of
third and first number is 10 and fourth number exceeds the second by 4. One of the number is
(A) 25
(B) 21
(C) 31
(D) 26​

Answer 1

Answer:

a) 25

Step-by-step explanation:

let four numbers be a,b,c,d.

given sum of four numbers is 100

a+b+c+d=100 ->eq 1

average of first second and fourth is 24

(a+b+d)/3=24

a+b+d=24*3

a+b+d=72 ->eq 2

sub a+b+d value in eq 1

a+b+c+d=100

72+c=100

c=100-72

c=28

the difference of third and first number is 10

c-a=10 -> eq 3

sub c value in eq 3

28-a=10

28-10=a

a=18

fourth number exceeds the second by four

d=b+4 -> eq 4

from eq 2

a+b+d=72

sub à and d in eq 2

18+b+b+4=72

2b+22=72

2b=72-22

2b=50

b=25

sub b in eq 4

d=b+4

d=25+4

d=29

therefore four values are 18,25,28,29

hence one of the value is a) 25