Answer:
a.
25 b+20 s=455...equation 1
b+s=20...equation 2, where b and s are the number of bicycle and in-line skate rentals per day.
b. The business had 11 bicycle rentals and 9 in-line skate rentals.
Explanation:
a.
Step 1: Determine an equation for total revenue today
Since the business rents bicycles and in-line skates, the total revenue will be as a result of amount received in revenue from renting the bicycles and in-line skates. This can be expressed as shown;
T=(B×b)+(S×s)
where;
T=total revenue
B=bicycle rental cost per day
b=number of bicycles
S=in-line skate rental cost per day
s=number of in-line skates
In our case;
T=$455
B=$25 per day
b=unknown
S=$20 per day
s=unknown
Replacing;
(25×b)+(20×s)=455
25 b+20 s=455...equation 1
Step 2: Determine an equation for total rentals today
The equation for the total number of rentals is;
R=b+s
where;
R=total number of rentals today
b=number of bicycles
s=number of in-line skates
In our case;
R=20
b=unknown
s=unknown
Replacing;
b+s=20...equation 2
b.
Step 3: Combine equation 1 and 2 ans solve simultaneously
1(25 b+20 s=455), multiplying equation 1 by 1=25 b+20 s=455
20(b+s=20), multiply equation 2 by 20=20 b+20 s=400
25 b+20 s=455
-
20 b+20 s=400
5 b+0 s=55
(5 b)/5=55/5=11
b=11, replace the value for b in equation 2 and solve;
(20×11)+20 s=400
220+20 s=400
20 s=400-220=180
20 s=180
s=(180/20)=9
The business had 11 bicycle rentals and 9 in-line skate rentals.
