Answer: 6 hours
Step-by-step explanation: If you write an equation for this scenario it would be y = 12+3x. 12 is the starting value and x represents how many hours the bike is rented, therefore 3 dollars would be added to the initial 12 each hour. So if Lucy spent $30 then it would change to 30= 12+3x. Now you essentially just need to work backwards. Rearrange the equation and move 12 to the left of the equal sign to make 30-12=3x. Combine vairable to make 18=3x. Divide 3x by 3 to isolate x and divide 18 by 3 as well to make it even. This looks like 18/3=3x/3. Meaning it would end up as 6=x.
Answer:
50 1/6% (50 and one sixth) or $22.92
Step-by-step explanation:
Answer: 
Step-by-step explanation:
First, we need to find the common denominator
The easiest way to do this is by multiplying the two given denominators, which are 2 and 5.
2 × 5 = 10
So, our common denominator is 10. Then, multiply the numerators of the two fractions by 2 and 5. Here's why:
=
We multiplied the top and bottom by 2 to make sure our new fraction stays equivalent to the original fraction.
Do the same thing for the other one:
= 
Finally, subtract the two fractions to find the difference between the two times:
= 
The reason we used the common denominator is because we can only add or subtract fractions if they have the same denominator.
Answer:
Temperature after 12 hours = 25°C
Step-by-step explanation:
Given:
Current tempreture = -23°C
Tempreture incresing rate = 4°C per hour
Total time = 12 hour
Find:
Temperature after 12 hours
Computation:
Temperature after 12 hours = Current tempreture + (Tempreture incresing rate)(Total time)
Temperature after 12 hours = -23 + (4)(12)
Temperature after 12 hours = -23 + 48
Temperature after 12 hours = 25°C