The common difference is d = 4 because we add 4 to each term to get the next one.
The starting term is a1 = 3
The nth term of this arithmetic sequence is
an = a1 + d(n-1)
an = 3 + 4(n-1)
an = 3 + 4n-4
an = 4n - 1
Plug in n = 25 to find the 25th term
an = 4n - 1
a25 = 4*25 - 1
a25 = 100 - 1
a25 = 99
So we're summing the series : 3+7+11+15+...+99
We could write out all the terms and add them all up. That's a lot more work than needed though. Luckily we have a handy formula to make things a lot better
The sum of the first n terms is Sn. The formula for Sn is
Sn = n*(a1+an)/2
Plug in n = 25 to get
Sn = n*(a1+an)/2
S25 = 25*(a1+a25)/2
Then plug in a1 = 3 and a25 = 99. Then compute to simplify
S25 = 25*(a1+a25)/2
S25 = 25*(3+99)/2
S25 = 25*(102)/2
S25 = 2550/2
S25 = 1275
The final answer is 1275
15cm if it’s a right triangle
Answer:
x = 20
Step-by-step explanation:
given f(x) = 
, we have to solve
= 4
Square both sides
()² = 4²
x - 4 = 16 ( add 4 to both sides )
x = 20
As a check
= 
= 4 ← correct
Answer:
Part 1) An equation is 15.7=3p+1
Part 2) The approximate population in 1950 was 4.9 million people
Step-by-step explanation:
Let
p -----> the population in 1950 in million people
y -----> the population in 2003 in million people
we know that
y=3p+1 -----> equation A
y=15.7 ----> equation B
substitute equation B in equation A and solve for x
15.7=3p+1
3p=15.7-1
3p=14.7
p=4.9
therefore
The approximate population in 1950 was 4.9 million people
1 month 29 days but if the month have 29 days each then the it will be 2 months
