we know that Bob can do the whole job in 14 hours, how much of the work has he done in 1 hour only? well since he can do the whole lot in 14 hours in 1 hour he has only done 1/14 th of the job.
we know that James can do it in 18 hours, a bit slower, so in 1 hour he has done only 1/18 th of the job.
let's say it takes both of them working together say "t" hours, so in 1 hour Bob has done (1/14) of the work whilst James has done (1/18) of the work, the whole work being t/t or 1 whole, so for just one hour that'd 1/t done by both Bob and James.

A car travels at an average speed of 48 miles per hour. how long does it take to travel 204 miles?It takes it 4.25 hours
Let us denote the number of boys in the glee club with X and the number of girls with Y.There are 84 students in the glee club, which means that the following equation can be written:X+Y=84We also now that there are 12 more boys than girls, so:X=Y+12We can rewrite the first equation like:(Y+12)+Y=842Y+12=842Y=62Y=62/2=31X=31+12=43So, the ratio of the number of girls to the number of boys is: Y/X=31/43
Read more on Brainly.com -
brainly.com/question/4711779#readmore
Answer:
b. You would conclude that the differences in the average scores can be traced to differences in the working memory of the two groups.
Step-by-step explanation:
Though the average scores of the two sets could have lead to various conditions, but retentive ability deminishes with respect to an increase in age. With respect to the age of the elderly people involved, it is expected that some of them would not be able to retain information for a long period of time. Thus, their average score is 72%.
The college students' are younger, so it is expected that they should be able to retain more information. That ability is one of the reasons why their average score is 85%.
It can be concluded from the research that the differences in the average scores is probably due to the working memory of the two groups.
can you show me what the math problem is?