Answer:
y =
x²
Step-by-step explanation:
Given that y and x² are directly proportional then the equation relating them is
y = kx² ← k is the constant of proportion
When x = 2
y = k × 2² = 4k
When x = 5
y = k × 5² = 25k
Then
25k - 4k = 20 ( difference between values is 20 )
21k = 20 ( divide both sides by 21 )
k = 
y =
x² ← equation of proportion
Given:
The sum of two terms of GP is 6 and that of first four terms is 
To find:
The sum of first six terms.
Solution:
We have,


Sum of first n terms of a GP is
...(i)
Putting n=2, we get


...(ii)
Putting n=4, we get



(Using (ii))
Divide both sides by 6.
Taking square root on both sides, we get

Case 1: If r is positive, then using (ii) we get
The sum of first 6 terms is




Case 2: If r is negative, then using (ii) we get
The sum of first 6 terms is




Therefore, the sum of the first six terms is 7.875.
Answer:
6.24
Step-by-step explanation:
A= 18.42g, B = 5.8g,C = 0.75g
Total = 18.42 + 5.8 + 0.75
= 24.97g
Then divided into four equal parts
= 24.97g/4
= 6.2425g
= 6.24g
8 times 3 equals 23 and that is one of the answers
First it was 186,000 and then the second year it was 202,000 what is the expenses is 16000