john types 20 pages in 40 min, sue types 20 pages in 30 min, bob types 20 pages in 24 min. working togehter how long to type 20 paqes
john types 20/40 or 1/2 page/min
Sue types 20/30 or 2/3 page/min
Bob types 20/24 or 5/6 page/min
combined rate = 1/2 + 2/3 + 5/6 or 2 pages per minute
time at combined rate = 20/2 or 10 minutes
To find out how long it would take for John, Sue, and Bob to type 20 pages together, we can calculate their individual page typing rates and then add them up. Then, we can use the combined typing rate to determine the time they would need to complete the task.
First, let's calculate their individual page typing rates:
John's page typing rate: 20 pages / 40 minutes = 0.5 pages per minute
Sue's page typing rate: 20 pages / 30 minutes = 0.67 pages per minute
Bob's page typing rate: 20 pages / 24 minutes = 0.83 pages per minute
Next, let's determine their combined typing rate by adding up their individual typing rates:
Combined typing rate = John's rate + Sue's rate + Bob's rate
Combined typing rate = 0.5 + 0.67 + 0.83 = 2 pages per minute
Finally, we can use the combined typing rate to find out how long it would take to type 20 pages:
Time needed = Number of pages / Combined typing rate
Time needed = 20 pages / 2 pages per minute = 10 minutes
Therefore, it would take John, Sue, and Bob 10 minutes to type 20 pages together.