Riyad can complete an assignment in 2 hours while omar can do the same assignment in 3 hours .they work together for an hour ,after which riyad left and omar had to finish the rest of the work alone. how much time in minutes will omar will require to finish the rest of the work?

In an hour Riyad can finish 1/2 of the assignment and Omar can finish 1/3 of it. Let x be the amount of time it will take Omar to finish the work. The equation that would best relate the conditions above is,
                        (1/2 + 1/3)(1) + (1/3)(x) = 1
The value of x from the equation is 0.5 hours. Therefore, it will take Omar another 30 minutes to finish the work.