Jack delivered 90 circulars in 20 min at this rate how long will it take him to deliver 135

Answer: 30

Step-by-step explanation: So if you take 90 divided by 20, you have 4.5. If you add 10 more mins to 20 which leaves you with 30mins, you take that and divide it by 4.5 you would end up with 135 which shows it's right.

Another way you could do this is by taking 135 and dividing it by 90, which will give you 1.5. Your gonna take 1.5 and times it by 20, which will give you 30.