Exercise 26. Review 1. Add 81, 5, 42, 63. 2. Change to lowest terms: 34, 12, 15, 18. 3. Reduce to improper fractions: 4. Change to mixed numbers: 5. Which is the larger, or 8 16 32 81, 162, 66, 37. 40, 18, 19, 25, 32. 16 5 of a thing? 7. Find the cost of 4 yards of ribbon at 37 cents a yard. 10. Find the cost of 6 cans of pork and beans at 121⁄2c a can. 11. Mrs. Adams bought 8 electric iron at 11 cents a foot. 12. Ethel weighed 52 The next year she gained at the end of the year? feet of insulated wire for her Find the cost. pounds when she was 8 years old. 4 pounds. What was her weight 13. Harry weighed 53 pounds when he was 8 years old and 57 pounds when he was 9 years old. How many pounds did he gain during that year? 14. Howard bought yard of oilcloth at 65 cents a yard. Find the cost to the nearest cent. 15. Dorothy bought two "squares" of bacon weighing 12 pounds and 17 pounds. What was the combined weight of the two pieces? How much did they both cost at 32 cents a pound? 16. Blanche bought 3 yards of lace at 62 cents a yard. Find the cost to the nearest cent. 17. Find the cost of a chicken weighing 4 pounds 7 ounces, at 30 cents a pound. Boil sugar, chocolate and milk until the candy, when dropped in water, makes a soft ball. Take from stove, add butter and set the pan to cool in water. Stir until thick; add flavoring and nuts, and pour into buttered tin. 1. The girls decided to make enough fudge for 20 pieces each. Find the amounts of each ingredient which they would need to make that amount. Eleanor's Recipe for Peanut Brittle cup granulated sugar 4 cups shelled peanuts rolled under rolling pin Stir sugar in a saucepan on the stove until melted; put in the peanuts, stir quickly, and pour into a buttered dish. 2. Each girl made this candy by herself and made of the recipe. Find the amount of each ingredient used by each girl. 3. Find the amount of each of the ingredients used by all 3 girls. 4. The girls decided to make twice this recipe. Find the amount of each ingredient used. Exercise 28. Dividing a Fraction by an Integer Then÷2-x=. If we divide of an inch as shown in the figure by 2 (or ), each part is only as great. Make a drawing to show that ÷2=1×1=1. In each of these cases the numerator has remained the same, but the denominator has been multiplied by the integer. In each of these two cases the denominators have remained the same, but the numerators have been divided by the integer 2. Use other fractions and other integers if necessary to show the PRINCIPLE: If a fraction is to be divided by an integer, if possible divide the numerator of the fraction by the integer, otherwise multiply the denominator of the fraction by the integer. 21. Three pupils buy together pound of notebook paper. What part of a pound is each one's share? 22. Joseph cut 8 score cards from sheet of card board. What part of a sheet was each score card? 23. Mary cut cake into 12 pieces. Each piece was what part of the whole cake? 24. Jean used of an opened can of enamel, full, in painting her golf balls. What part of a can of enamel did she use? 25. Majorie took out of a box of raisins cookies. What part of a box did she use? full to use for Exercise 29. Dividing an Integer by a Fraction In the illustration of a sheet of paper at the left, the shaded portion is what fraction of the whole sheet of paper? The whole sheet is divided into how many fifths? The fraction 3 fifths is contained in the whole sheet (5 fifths) how many times? Suggestion: The remainder, 2 fifths, is what part of the fraction 3 fifths? From this illustration we see that the fraction is contained in the whole sheet (or g) 13 or times. 1. What is 2÷? Then 1÷3=3. 13. Then 2÷3=2x-10, or 31. = 2. What is 5÷3? Draw a figure similar to the illustration above to show that 1÷3 is 2. Then 5÷3=5×3= 15, or 71⁄2. We see that in each of these examples, the division example has been changed into a multiplication example. In the illustration 2÷=2×3, the divisor has become inverted, the denominator of becoming the numerator of ğ and the numerator of becoming the denominator of §. Thus we see the PRINCIPLE: To divide an integer by a fraction, multiply the integer by the fraction inverted. 22. A drawing teacher has on hand 12 yards of narrow ribbon. How many pupils can she supply with for their calendars? yard each 23. Out of a class of 20 how many pupils must wait for a later supply, if each is to haveyard of cord, and the drawing teacher has only 8 yards? 24. How many book ends each requiring square foot of tin may be cut from a sheet containing 6 square feet? 25. Allowing yard each, how many towels can be cut from a 7-yard piece of linen? |