Name: _______________________
Date: ________________________
Extra Practice on Word Problems
1. With a tail wind, a plane flew 1000 miles in 2 hours. The plane, flying directly
against that same wind, required 2.5 hours for the return trip. Find the speed of the plane
and the speed of the wind.
2. With a tail wind, a jet plane flew 2400 miles in 4 hours, but it required 6 hours for the
return trip against the wind. Find the speed of the plane and the speed of the wind.
3. A boy needed 45 minutes to paddle his canoe 3 miles upstream and 30 minutes to
return downstream. Find the rate at which the boy could paddle in still water and the rate
of the stream. (Hint: Change from minutes to hours)
4. A man needed one hour to row one mile upstream, but only 12 minutes to row back
down. Find his rowing rate (in still water) and the rate of the current.
5. A druggist has 10 ounces of a 20% solution of argyrols. How many ounces of an 8%
argyrols solution should he add to form a 12% argyrols solution?
6. How many quarts of pure alcohol must be added to 5 quarts of 40% alcohol solution
to make a 50% alcohol solution?
7. A certain alloy contains 65% copper and a second alloy 40% copper. How many
pounds of the second alloy must be added to 54 pounds of the first to form an alloy that is
55% copper?
8. How much distilled water should a nurse add to reduce 16 ounces of a 25% solution of
antiseptic to a solution that is 10% antiseptic?
9. A chemist has a 50% sulfuric acid solution and a 10% sulfuric acid solution. How
much of each should he use to make 100 cubic centimeters of a 20% sulfuric acid
solution?
10. How much water must be evaporated from 150 pounds of a 4% salt solution to leave
a solution that is 6% salt?
11. A car radiator contains 15 quarts of a 25% antifreeze solution. How many quarts
must be drained off and replaced by a 75% antifreeze solution to leave the radiator filled
with a 55% antifreeze solution?
12. Tom Swift has a solution that is 60% alcohol. After he draws off 5 liters and
replaces it with 5 liters of alcohol the resulting solution is 85% alcohol. How many liters
does he have?
13. The sum of the digits of a two-digit numeral is 9. When the digits are interchanged,
the new numeral represents a number that exceeds the original number by 27. Find the
original number.
14. The sum of the two digits of a number is 8. If 18 is added to the number, the digits
of the new numeral are those of the original numeral, but they appear in reverse order.
Find the original number.
15. Fifteen years from now, Mr. Thomas will be twice as old as Mrs. Thomas is now,
whereas Mrs. Thomas will then be as old as Mr. Thomas will be 10 years from now.
How old are Mr. and Mrs. Thomas?