Answer:
4
Step-by-step explanation:
Variable: X = Unknown Number
2x + 4 = x + 8
2x - x = 8 - 4
x = 4
Check:
2(4) + 4 = 4 + 8
8 + 4 = 12
12 = 12
So n will be the unknown, and the expression is:
6n = 24
from where we can find the number n:
n = 24/6
n = 4
Answer:
495
Step-by-step explanation:
In order to find the sum of the first 18 terms you have to find the 18th term and the first term using the equation given.
a1=3(1)-1 a1=2
a18=3(18)-1 a18= 53
Then plug in 53 for an, 18 for n, and 2 in for a1 in the sum equation: Sn=n/2(a1+an)
Sn=18/2(2+53) Solve for sn= 495
Answer:
9:15
Step-by-step explanation:

300
divide 3000 by 10 to get a tenth of 3000