# Grade - examples - page 209

1. Iron density Calculate the weight of a 2 m long rail pipe with an internal diameter of 10 cm and a wall thickness of 3 mm. The iron density is p = 7.8 g/cm3.
2. Bucket The bucket half filled with water weighs 5.55 kg, the full bucket weighs 9.85 kg. How much does the bucket weigh?
3. Precious metals In 2006-2009, the value of precious metals changed rapidly. The data in the following table represent the total rate of return (in percentage) for platinum, gold, an silver from 2006 through 2009: Year Platinum Gold Silver 2009 62.7 25.0 56.8 2008 -41.3 4
4. Banknotes How many different ways can the cashier payout € 310 if he uses only 50 and 20 euro banknotes? Find all solutions.
5. Distance problem A=(x, x) B=(1,4) Distance AB=√5, find x;
6. Outside temperature The temperature outside was 57 degree Fahrenheit. During the next few hours it decreased by 18 degrees and then increased by 23 degrees. Find new temperature.
7. Temperature conversion The normal human body temperature is 98.6 degrees Fahrenheit. What is the temperature in degrees Celcius?
8. The pool The pool contains 220 m3 of water. The pool can be emptied either: a) 10 hours of pipe B and 8 hours of pipe A, or b) 10 hours of pipe A and 7 hours of pipe B. How many cubic meters of water will flow in 1 hour from pipe A and how many from pipe B?
9. Bed time Tiffany was 5 years old; her week night bedtime grew by ¼ hour each year. If, at age 18, her curfew time is 11pm, what was her bed time when she was 5 years old?
10. Circus On the circus performance was 150 people. Men were 10 less than women and children 50 more than adults. How many children were in the circus?
11. Inquality Solve inequality: 3x + 6 > 14
12. Simplify 2 Simplify expression: 5ab-7+3ba-9
13. Expression 8 Evaluate this expressions: a) 5[3 + 4(2.8 - 3)] b) 5×(8-4)÷4-2
14. No smoke Tobacco company NO-SMOKE adorned its stand at the cigarette-type trade fair with the cigarette-shaped. The dimensions of which were 20 times the size of a regular cigarette. The regular cigarette contains 0.8 mg of nicotine. How much nicotine would a giant
15. Volume of ball Find the volume of a volleyball that has a radius of 4 1/2 decimeters. Use 22/7 for π
16. Parallelogram Rhomboid (parallelogram) has a longer side of 50 cm long. The size of its one height is four times the size of its second height. Calculate the length of the shorter side of this rhomboid in the centimeters.
17. Banknotes Eva deposit 7800 USD in 50 banknotes in the bank. They had value 100 USD and 200 USD. How many were they?
18. Reminder and quotient There are given numbers A = 135, B = 315. Find the smallest natural number R greater than 1 so that the proportions R:A, R:B are with the remainder 1.
19. It is 2 It is 90 feet from home plate to first base on a baseball diamond. What is the area of the baseball diamond in square yards?
20. An oil An oil drum is cut in half. One half is used as a water trough. Use the dimensions; length 82cm, width 56cm to estimate the capacity of the water trough in liters.

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