Answer: when u doing area know you are multiplying hope i help
Step-by-step explanation:
Answer:
an = 1/2 (n) (n+1)
Step-by-step explanation:
1,3,6,10,.........
3-1=2
6-3=3
Each term is different so there is no common difference. It is not an arithmetic sequence
3/1=3
6/3 =2
Each term is different so there is no common ratio. It is not a geometric sequence
1 3 6 10
+2 +3 +4
a1 = 1
a2 = 3
a3 = 6 = 2*3
a4 = 10 = 2*5
Solution
For this case we can use the following formula:

Where:
P= 400800 = present value
A= future value
r= 0.055 interest rate
n= 4, number of times that the interest is compund in a year (quarterly)
t= 4 years
Replacing we got:

then the interest would be: