Answer:
6 terms
Step-by-step explanation:
To find the number of terms we will use the formula:
Sn = a(1-r^n)/1-r
where a is the first term= 1
r is the common ratio = 2
Sn is the sum of series = 63
n is the number of terms = ?
Now substitute the values in the formula:
Sn = a(1-r^n)/1-r
63= 1(1-2^n)/1-2
63=1(1-2^n)/-1
63*-1 = 1(1-2^n)
-63 = 1-2^n
Now combine the constants:
-63-1= -2^n
-64= -2^n
64= 2^n
2^6 = 2^n
When the base are same powers are equal to each other.
6=n
Thus there are 6 terms....
