Answer:
135
Step-by-step explanation:
The sequence are:
a, 2a, 4a, 8a, 16a.....
the total value of the first three terms is 63
That is,
a + 2a + 4a = 63
7a = 63
a = 63/7
a = 9
work out the total value of the first four terms
First four terms are: a, 2a, 4a, 8a
Where,
First term, a = 9
Second term, 2a = 2*9 = 18
Third term, 4a = 4*9 = 36
Fourth term, 8a = 8*9 = 72
The total value of the first four terms = 9 + 18 + 36 + 72
= 135
The total value of the first four terms = 135
