Answer:
There are
five dollar bills and
ten dollar bills.
Step-by-step explanation:
Given:
Selling price of bicycle
.
The friend gave
five dollar bills and
ten dollar bills.
Total number of bills
.
To find: Number of five dollar bills and ten dollar bills the friend gave.
Solution:
The friend gave
five dollar bills and
ten dollar bills and the friend gave
bills in all.
So,
.

Selling price of bicycle
.
So, 
Putting the value of
from equation
in equation
.







Now, putting the value of
in equation
.


Hence, there are
five dollar bills and
ten dollar bills.
Answer:
see explanation
Step-by-step explanation:
The sum of the first 9 consecutive odd numbers is
1 + 3 + 5 + 7 + 9 + 11 + 13 + 15 + 17 = 81