Answer:
c. t = 18; the Chang family has been driving for 18 hours
Step-by-step explanation:
Given:
D(t) = 2,280 - 60t
Find t when D(t) = 1,200
D(t) = 2,280 - 60t
1200 = 2280 - 60t
Subtract 2280 from both sides of the equation
1200 - 2,280 = 2280 - 60t - 2,280
- 1080 = - 60t
Divide both sides by -60
- 1080 / -60 = - 60t / -60
18 = t
t = 18
This means the Chang family has been driving for 18 hours
c. t = 18; the Chang family has been driving for 18 hours
<span>When adding up fractions, the idea is to bring them to a common denominator. In our case, the common denominator is 12. So we must amplify each fraction in order to bring its denominator to 12. 1/6 becomes 1*2/6*2 = 2/12. 2/3 becomes 2*4/3*4. 1/4 becomes 1*3/4*3. When we sum them up we get 2/12 + 8/12 + 3/13 or 13/12, which is (12+1)/12 or 12/12 + 1/12 or 1+ 1/12. So the answer is C.</span>
Answer:
I believe the answer is D
Step-by-step explanation:
