Suppose that this person drives at r mph going to the mountains, and gets there in 12 hours. Returning, this person drives at (r+20) mph and gets home in 8 hours. We don't know the distance yet, but can solve for the initial speed, r, by setting
d = 12r = (r+20)(8). Solving for r, r=40 mph (going) and (40+20)mph = 60 mph (returning. Since d=12 r, d = (12 hrs)(40 mph) = 480 miles (answer).
Answer:
X= 10, 20, 30, 40, 50, 60
Step-by-step explanation:thats
thats all i know
Let x be the unknown number.
<span>7x + 668 </span><<span> 2000</span> => 7x plus 668 is less than 2000
where:
7x => x represents the number of cans to be collected in 7 days
668 is the number of cans already collected.
2000 is the target number of cans.
7x + 668 < 2000
- 668 -668
7x < 1332
÷7 ÷7
x < 190.30
or
x < 190
To check:
7x + 668 < 2000
7(190) + 668 < 2000
1330 + 668 < 2000
1998 < 2000
