1 + (-5) becomes 1 - 5 because you are adding a negative number.
1 - 5 is -4
3x-13=305
3x=305+13
3x=318
(3x)÷3=318÷3
x=106
check.. (3×106)-13=305
318-13=305
305=305
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.
There are 6 nickels and 14 pennies.
There are 20 total coins.
The ratio of nickels to coins is 6:20.
Both of these are divisible by 2, so we can reduce this to 3:10.
A tangent contains no chords
