plz............ explain......
1)Average age of a group of 10 students is 20 years,
if average age increased by two years when two new
students are joined then the average age of two new students
a) 84 b) 64 c) 32 d) 42
2)If x is inversely related with square of y for x = 1 and y = 2 then find the value of x when y = 6
a) 3 b) 9 c)1\3 d)1\9
Avg age of ten students = 20 years, Sum of Ages = 200
Avg age of 12 = 22, Sum of Ages = 264
Increase in Sum of Age = 64
Average increase = 32
x= a/y^2
when X=1, Y=2, a=4
Thus the equation is x=4/y^2
When y=6,
X= 4/36
x = 1/9
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