Answer:
Step-by-step explanation:
As
7.2, a, b, 3 are in A.P
As we know common difference of the arithmetic sequence is the difference between the successive term and its preceding term, which is always constant
so
a -7.2 = b - a
a + a = b + 7.2
2a = b + 7.2
b = 2a - 7.2
also
a, b, 3 are in A.P
b - a = 3 - b
b + b = 3 + a
2b = 3 + a
Putting b = 2a - 7.2 in the equation 2b = 3 + a to find the value of 'a'.
2b = 3 + a
2 (2a - 7.2) = 3 + a
4a - 14.4 = 3 + a
3a = 3 + 14.4
3a = 17.4
Dividing the equation by 3
3a ÷ 3 = 17.4 ÷ 3
a = 5.8
Putting a = 5.8 in the equation b = 2a - 7.2
b = 2a - 7.2
= 2(5.8) - 7.2
= 11.6 - 7.2
b = 4.4
Therefore,
