Power = voltage x current (in watts) = 120 volts x 1/2 amp = 60 watts.

For the regular 40 hours, the worker earns $7.20 x 40 = $288.00. If the regular wage is S7.20 per hour, then overtime paid at time and a half is $7.20 x 1.5 = S10.80. The three hours of overtime earn the worker a total of $32.40. Add the regular time wages to the overtime wages:
$288.00 - S32.40= $320.40 total pay

First find the amount of the decline in traffic.11,200 cars- 10,044 cars = 1,156 fewer cars per dayNow multiply the amount of traffic decrease by 100 and then divide it by the amount of original traffic. This will yield the percentage decrease without further calculation.
1,156x100=115,600
115,600 - 11,200 = 10.3% decrease

If the original mixture is 33 % (or 1/3) acetone, then 1/3 of the mixture of 12 liters, or 4 liters, is acetone.
The fraction 4/12 represents the ratio of acetone to total mixture. If the total mixture is increased by x liters, the ratio of acetone to total mixture becomes 4/(12+x).This is to be equal to 25% (or 1/4).
4 / 12+x = 1 / 4
To undo the divisions on both sides of the equation, multiply both sides by 4 and also by 12+x.
4/12+x * 4(12+x)/1
= 1/4 * 4(12+x)/1
16 = 12+x
The isolate x on one side of the equation, subtract 12 from both sides 16-12 = 12 + x-12 4=x