Answer:
The answer is:
30 minutes.
Step-by-step explanation:
We are given the following information:
at 160 m/min, tool life = 5 min.
at 120 m/min, tool life = 17 min.
This means that as the speed reduced from 160 m/min to 120 m/min, the tool life increased from 5 min. to 17 min, hence the difference between the changes are:
speed = 160 - 120 = 40 m/min
tool life = 17 - 5 = 12 min.
Therefore, it can be concluded that a change of speed of 40 m/min, increases the tool life by 12 min.
40 m/min = 12 min
∴ 1 m/min = 12/40 min.
∴ 100 m/min = 12/40 × 100 = 0.3 × 100 =30 min.
Answer:
Step-by-step explanation:
- <em>Percent change is the difference in numbers divided by initial number converted to percent value.</em>
<u>Percent increase:</u>
<u>Percent decrease:</u>
- (70 - 50)/70*100% = 28.57%
<u>Compare:</u>
Answer:
a) 3C1 * 12 C1 / 15 C2
b) 1 - 12C2 / 15C2
Step-by-step explanation:
Được
Viên bi đỏ = 3
Viên bi trắng = 5
Viên bi xanh = 7
Hai quả bóng được rút ra một cách ngẫu nhiên
a) Có 1 bi đỏ
3C1 * 12 C1 / 15 C2
b) Có ít nhất 1 viên bi đỏ trong số 2 viên lấy ra.
Số kết quả của việc chọn hai quả bóng trong số 15 quả bóng = 15 C2
Số kết quả của việc chọn 0 quả bóng đỏ = 15C12
Xác suất chọn được ít nhất 1 viên bi đỏ = 1 - 12C2 / 15C2
Answer:
Step-by-step explanation:
<u>Given relationships:</u>
DE = 2 AC
- Incorrect. Should be DE = 1/2 AC
DE║AC
m∠BCA = 2(m∠BED)
- Incorrect. Should be m∠BCA = m∠BED
DE = AC
- Incorrect. Should be DE = 1/2 AC
<span>ow far does the first car go in the 2 hours head start it gets?
Now, at t = 2 hours, both cars are moving. How much faster is the second car than the first car? How long will it take to recover the head start? You can determine this by dividing the head start by the difference in the two speeds. If car 1 has a 20 mile head start, and car 2 is 5 mph faster, then it will take 20/5 = 4 hours to catch up.
</span>You could also write two equations, one for each car, showing how far they have gone in a variable amount of time. Set the two equations equal to each other and solve for the value of the time. Note that the second car's equation will use (t-2) for the time, because it doesn't start driving until t = 2.
