Shawna does her maths homework every night. Last night, Shawna spent 45 minutes solving 15 maths problems. Tonight, she needs to solve 10 maths problems.If she does them at the same rate, how many minutes will Shawna spend solving tonight's maths problems?

Miko took 1 h 15 min to finish her homework.Keddy took 50 min to finish the same homework.How much longer did Miko spend on her homework than Keddy?Express your answer in minutes.

Jill is a writing tutor at her local community center. She has spent $400 on advertisements, and she pays the community center $20 per hour to use its facilities. She charges her clients $60 per hour.How many hours must Jill tutor for the amount she brings in to equal the amount she spends? hours

Wendy can build a doghouse in 15 hours, and Miguel can build an identical doghouse in 10 hours. How many hours will it take Wendy and Miguel, working together at their respective constant rates, to build a doghouse?

Eight engineers with 2 technicians can design a house in 7 hours, which 25 engineers with 13 technicians can do in 2 hours. What fraction of the whole work, can be done in 1 hour by 11 engineers with 20 technicians?

Darrell's math class starts at 10:40 A.M. and lasts for 1 hour. After math class, Darrell has recess for 15 minutes. What time does Darrell's recess end?