Time - 8th grade (13y) - examples
- Adam and Ben
When Ben is so many years old to Adam today, Adam will be 23 years old. When Adam was as old as Ben, Ben was two years old. How old is today Ben and Adam?
- Two boats
The sightseeing boat sail at 25 km / h. The cruise take 6 hours. How long the another boat sails at 60 km/h?
A pond with two open floodgates will emptied in 20 days. A larger floodgate will emptied whole pond in 30 days. For how long would he be emptied with a smaller floodgate.
The tank is filled with a larger pump in 12 hours and with scond pump in 15 hours. For how long does the tank fill when both pumps are switched on at the same time?
Two hours 24 students harvested chestnuts on 36 acres. How many square meters harvested one student per hour?
- Father and son
Father is 48 years old, son 23. When will be the father twice older than a son?
The grandfather is three years older than an grandmother. The average age of the grandmother, the grandfather and their seven grandchildren is 28 years. The grandchildren have a total of 105 years. Calculate how old is grandfather.
Route is long 203 km and the first day first regiment went at an average speed 20 km/h and journey back 19 km/h. The second day went second regiment same route at an average speed 18 km/h there and back. Which regiment will take route longer?
A man drinks a barrel of water for 31 days, woman for 58 days, for how many days they drink barrel together?
- Painter Pavel
Painter Pavel painted the fence for 20 hours and painter Petr the same fence painted for 17 h. How long should take painted the fence together?
- Christmas Day
In leap years was 53 Sundays. On what day of the week fell to Christmas Day?
Two workers fulfill a certain task when working together for 7 days, the first if he worked himself done work in 18 days. How many days will do whole job a second worker?
The first tributary fill pool with water in 15 hours. The second tributary fill pool in 10 hours. For how many hours the pool is filled with both tributaries?
- Road repair
Road repair took 16 days for 34 workers if they worked 6 hours a day. How many days take repair same road 33 workers if they work 6 per day?
Write time in minutes rounded to one decimal place: 1 h 42 m 22 s.
The vineyard can be sprayed first sprayer in 5 hours and with the second in 7 hours. How long would it take if we use sprayers both at once?
Monkey fell in 31 m deep well. Every day her scramble 3 meters, at night dropped back by 2 m. On that day it gets hangover from the well?
For every 5 minutes writes Dana 10 invitations, while Anna 14 invitations. How long will write together 120 invitations?
The tale of the Seven Ravens were seven brothers, each of whom was born exactly 1.5 years after the previous one. When the eldest of the brothers was 4-times older than the youngest, mother all curse. How old was seven ravens brothers when their mother cur
During the spring cleaning ladies going to wash windows. Mother takes wash all the windows 5 hours, the grandmother 3 times longer and Paula wash all windows in 5 hours. How many hours will spend washing the windows this "women's team" if working togethe