Answer:
3,672
Step-by-step explanation:
Given the sequence 6, 9, 12...
The sequence is an arithmetic sequence
first term a = 6
common difference d = 9 - 6 = 12 - 9 = 3
number of terms n = 48
Sn = n/2[2a+(n-1)d]
Substitute the given values
S48 = 48/2[2(6)+(48-1)(3)]
S48 = 24(12+(3*47))
S48 = 24(12+141)
S48 = 24(153)
S48 = 3,672
Hence the sum of the first 48terms is 3,672
