Question

twelve years ago the average age of a husband an wife was 20 years the average remain same today when they have 2 children what was the present age of the youngest child if they differ the age by 2 years?​

Answer 1

Answer:

7 year old

Step-by-step explanation:

current age husband=h, wife=w.

12 years ago, avg:20. so (h-12)+(w-12)=20*2=40

hence, current, h+w=40+24=64

for avg of family to be the same h+w+C1+C2=20*4=80

hence 64+C1+C2=80

so C1+C2=16

now, c2-c1=2.. C2=c1+2

so

C1+C1+2=16

2*C1=14

C1=7....

Answer 2

Answer:

12 years ago HUS and Wife Avg=20

current avg of family 4 members =20

avg=SUM OF THE OBSERVATION/ NO OF THE OBSERVATIOS

SUM=H+W+child+child/4

Hence-H+W+C+C=AVG×4

= 80

CURRENT AGE OF H+W= (20+12year=32)+20+12=32

64+C+C=80

EldC+younC=16

eldC-youC=2

- +

=2yc=14

=y=14/2=7

answer 7*