Since there is a common difference of one, this is an arithmetic sequence of the form a(n)=a+d(n-1) which in this case is:
a(n)=15+1(n-1)
All arithmetic sequences have a sum which is equal to the average of the first and last terms time the number of terms, mathematically:
s(n)=(2an+dn^2-dn)/2 (that is just the result of ((a+a+d(n-1))(n/2)) )
Since a=15 and d=1 this becomes:
s(n)=(30n+n^2-n)/2
s(n)=(n^2+29n)/2 so
s(10)=(100+290)/2
s(10)=195 logs
Answer:
C. -2
Step-by-step explanation:
The slopes of parallel lines are always the same.
GIVEN:
Cost of a taco and a cup of tea = $2.10
Cost of 2 tacos and 3 cup of tea = $5.15
ANSWER:
On solving eq(1), we get
Substitute the value of x in eq(2), we get
- 2(2.10 – y) + 3y = 5.15
- 4.20 – 2y + 3y = 5.15
- y = 5.15 – 4.20
- y = 0.95
So, x = 2.10 – 0.95
Hence, Cost of a taco is $1.15
So, <u>Correct choice</u> - [E] $1.15
In fraction that would be 3/4 because 15/20 simplified would be three quarters.
If thats not the answer, message me back and I will go out of my way to figure out the correct one. Thats my policy :)