`a+b=15`
The equations above relates the number of hours, a, Kevin spends doing homework each week and the number of hours he spends watching television each week. If kevin spends a total of 15 hours doing homework and watching television each week, what does the variable b represent?

x + y = 75 The equation above relates the number of minutes, x, Maria spends running each day and the number of minutes, y, she spends biking each day. In the equation, what does the number 75 represent?

Thirty children were asked about the number of hours they watched TV programmes in the previous week. The results were found as follows : : How many children watched television for 15 or more hours a week ?

Micro is paid $80 per day plus $15 per hour for overtime. If he works five days per week and wants to make a minimum of $520 this week, what is the fewest number of hours of overtime he must work ?

If 15 men take 21 days of 8 hours each to do a piece of work, then what is the number of days of 6 hours each that 21 women would take, if 3 women would do as much work as 2 men ?

In a certain factory, each day the expected number of accidents is related to the number of overtime hours by a linear equation. Suppose that on one day there were 1000 overtime hours logged and 8 accidents reported and on another day, there were 400 overtime hours logged and 5 accidents. What are the expected number of accidents when no overtime hours are logged?