# Examples for 7th grade (seventh) - page 71

1. Hamster cage
Ryan keeps his hamster cage on his dresser. The area of the top of Ryan's dresser is 1 2\3 as large as the area of the bottom of his hamster cage. The area of the dresser top is 960 square inches. How many square inches of his dresser top are not covered b
2. Simple equation 3
24 = n • 27, solve for n
3. Hay bags
4 cows eat 16 hay bags in 5 days. How many bags will eat 5 cows in 7 days?
4. Five pumps
Three same pumps fill the tank with 50400 liters of diesel in 7 hours. How many liters of diesel will it take in 4 hours if we add two more of the same pumps and pump them the same way? How much more (or less) will they get if we add 2 of the same pumps a
5. Land area
A land area of Asia and Africa are in a 3: 2 ratio, the European and African are is 1:3. What are the proportions of Asia, Africa, and Europe?
6. Mail train
The speed of mail train is 1370 meter per minute. Express it in miles per hour correct to three significant figure . Given that 1 meter =39.37 inches.
7. Evaluate expression
Evaluate expression using BODMAS rule: 1 1/4+1 1/5÷3/5-5/8
8. Volume of cube
Solve the volume of a cube with width 26cm .
9. Balls groups
Karel pulled the balls out of his pocket and divide it into the groups. He could divide them in four, six or seven, and no ball ever left. How little could be a ball?
10. Four workers
Four workers will lay the floor of the gym in six hours. After an hour of working together, one of the workers left to the doctor. How long before the remaining three workers finish their work?
11. Glass panel
A rectangular glass panel with dimensions of 72 cm and 96 cm will cut the glazier on the largest square possible. What is the length of the side of each square? How many squares does the glazier cut?
12. Lcm of three numbers
What is the Lcm of 120 15 and 5
13. Money 6
Lita had some money. She spent 1/2 of it on a hand bag and 1/3 of the remainder of the blouse. She had 260.00. How much money did she have at start?
14. Parcel 4
To send a parcel by messenger within city limits costs 60 cents for the first pound and 48 cents for each additional pound. What is the cost, in cents, of sending a parcel weighing p=4 pounds?
15. Find the
Find the volume of a quadrangle prism high 2dm whose base is a square with a side 15cm.
16. Customer
A customer purchase three (3) writing pads from a store. She receive k9.70 change from a k10.00 note . How much was it's writing pad cost?
17. Interior designer
To make draperies an interior designer needs 11 1/4 yards of material for the den and 8 1/2 yards for the living room. If material comes only in 20 yard bolts, how much will be left over after completing both sets of draperies?
18. Snowman 3
During the last winter carnival, the local college students built a 30- foot snowman out of 109 tons of snow. How much snow will be needed to build a 36- foot snowman this year?
19. In and out
The empty tank is filled in 12 minutes and empty in 16 minutes. How long does it take to fill if we forgot to close the drain? If the tank has 1000 l.
20. Together
Grandfather, father, and son are carpenters. They decided to make a wardrobe. Father produces it for 12 hours, his son for 15 hours, and grandfather for 10 hours. How long will they make it together?

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