An irrigation pump can pump 250 liters of water per minute. How many hours should the system work to water a rectangular field 75 m by 135 m to a depth of 3 cm?
4. A spider and a fly are in a room that has length 8 m, width 4 m, and height 4 m. The spider is on one end wall 1 cm from the floor midway from the two side walls. The fly is caught in the spider’s web on the other end wall 1 cm from the ceiling and also midway from the two side walls. What is the shortest distance the spider can walk to enjoy his meal? (Hint: Draw a two-dimensional picture.)
To find out how many hours the irrigation pump system should work to water the rectangular field, we need to calculate the total volume of water needed to achieve a depth of 3 cm.
First, let's convert the dimensions of the field from meters to centimeters for consistency. The dimensions of the field are now 7500 cm by 13500 cm.
The volume of water needed can be calculated using the formula: volume = length * width * depth.
So the volume of water needed = 7500 cm * 13500 cm * 3 cm = 3037500000 cm^3.
To convert cubic centimeters to liters, we need to divide by 1000: 3037500000 cm^3 ÷ 1000 = 3037500 liters.
Now, we can calculate the time required to pump 3037500 liters of water at a rate of 250 liters per minute.
Time = volume / flow rate = 3037500 liters / 250 liters per minute.
To convert minutes to hours, we divide by 60: (3037500 / 250) / 60 = 203 hours.
Therefore, the system should work for approximately 203 hours to water the rectangular field to a depth of 3 cm.