n) The mean of three numbers is 25. The mean of other four numbers is 48.
mean of all the numbers.
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Answers
Step-by-step explanation:
X + X ' + X" / 3 = 25 ( given )
X + X ' + X" = 75
Y + Y ' + Y " / 3 = 48 ( given )
Y + Y ' + Y " = 144
now ,
X + X ' + X" + Y + Y ' + Y " = 75 + 144
X + X ' + X" + Y + Y ' + Y " = 219
for calculating mean : divide by 6
X + X ' + X" + Y + Y ' + Y " / 6 = 219 / 6
Answer:
Step-by-step explanation:
We know that, mean = sum of all observations ...................eqn(1)
total number of observations
CASE 1 :
Given , that mean of three numbers is 25
ie, from eqn (1) we can write it as
25 = sum of all observations in CASE 1
3
ie, 3 × 25 = sum of all observations in CASE 1
ie, sum of all observations in CASE 1 = 75
CASE 2 :
Here also , from eqn (1) , we get,
48 = sum of all observations in CASE 2
4
ie, 48 × 4 = sum of all observations in CASE 2
ie, sum of all observations in CASE 2 = 192
∴ Mean of all the numbers = sum of observations of CASE 1 and CASE 2
total no: of observations in CASE 1 & CASE 2
= 75 + 192
3 + 4
= 267 / 7