In a family of 5 males and a few ladies, the average monthly consumption of grain per head is 9 kg. If the average monthly consumption per head be 12 kg in the case of males and 8 kg in the case of females, find the number of females in the family.
Answers
Given,
Number of male members in the family = 5
Average monthly consumption of grain per head = 9 kg
Average in case of males = 12 kg
Average in case of females = 8 kg
To Find,
The number of females in the family.
Solution,
Let us assume that the number of females is y and the consumption of grains by men is m and that of females is f.
So,
(m+f)/(5+y) = 9
m+f = 9(5+y)---(i)
Also
m/5 = 12
m = 60
f/y = 8
f = 8y
Substituting these values in (i)
60+8y = 9(5+y)
60-45 = y
y = 15
Hence, the number of females in the family is 15.
Answer:
GIVEN: Average = Sum of n numbers/n
TO FIND: the number of females in the family .
∵ average monthly consumption of rice is 10 kg for females,
10 = Total consumption by females/4
⇒ Total consumption by females = 10 × 4 = 40
Also, the average monthly consumption of rice is 16 kg for males,
16 = Total consumption by males/x
⇒ Total consumption by females = 16 × x = 16x
Average monthly consumption of rice per head in the family = 12Kg
⇒ Total number of members = 4 + x
∴12=40+16x4+x∴12=40+16x4+x
⇒ 40 + 16x = 12 × (4 + x)
⇒ 40 + 16x = 48 + 12x
⇒ 4x = 8
⇒ x = 8/4 =2
∴ No. of females in the family = 2.
#SPJ2