SIMPLE NUMBERS. 1. A number that has no exact integral divisors except itself and 1, is called a prime number. 1, 2, 3, 5, 7, 11, are prime numbers. 2. Integral numbers that are not prime are said to be 4. If an integral number is expressed by two or more figures, and the right-hand figure is 5, the number is (a) Write all the prime numbers from 1 to 53 inclusive, and find their sum. *This means, find how many times $52 are contained in $7436. $52 are contained in $7436, 143 times. Story-A man paid $7436 for land at $52 an acre; there were 143 acres. †This means, find 1 fifty-second of $7436. 1 fifty-second of $7436 is $143. StoryA man paid $7436 for 52 acres of land; one acre cost $143. (k) Find the difference of 946g and 388. 6. Divide 7 by 3. This means Story.t (1) Find the quotient of 36 divided by 2. Story.‡ (m) 24 gallons)126 gallons. This means, find how many times 21 gallons are contained in 126 gal. (Change 21 and 126 to fourths.) Story.§ (n) 4)276 gallons. This means, find 1 fourth of 2761 gal lons. Story-In 276 gallons of milk; this was at the rate of days Mr. Smith sold gallons per day. *The pupil is expected to find by trial that he can change halves, thirds, and eighths, to twenty-fourths. See note (4) page 6, and problem 4, page 22. Mr. Brown put 36 bushels of peaches into -bushel baskets; there were baskets. Put 126 gal. of milk into 21-gal. cans. If 1 ton of coal is worth $2.45, 1 tenth of a ton of coal is worth 2.3 tons of coal are worth (b) Multiply $3.65 by 2.4.* (c) Multiply $52.8 by 3.2. (1 of $3.65 is $.365.) 2. I bought 73 yards of print at 6¢ a yd. and gave the salesman half a dollar; I should receive in change. (d) I bought 5.3 tons of coal at $4.20 a ton and gave the salesman 3 10-dollar bills. How much change should I receive? *Write the decimal point in each partial product immediately after making the figure that represents the tenths in that product. + This means, find how many times 5 tenths are contained in 475 tenths. This means, find 1 fifth of $47.5. 1. When two lines meet at a point, they are said to form an angle. 2. When a jackknife is half way open, the handle and blade form a right angle. If it is less than half way open, they form an angle. If it is more than half way open, but not fully open, they form an angle. right angles. 5. Rectangular means right-angled. 6. A rectangular figure, or rectangle, may be a square, or it may be an oblong. 7. A rectangle 6 inches by 6 inches is a 8. A rectangle 4 in. by 6 in. is an 9. A rectangular surface 4 feet by 6 feet is an area is square feet and its perimeter is feet. ; its 10. A rectangular surface 8 feet by 8 feet is a ; its area is square feet; its perimeter is ft. 11. Which has the greater area, a 5-in. square, or an oblong 4 in. by 6 in.? Compare their perimeters. Find the area and the perimeter of each of the following rectangular surfaces: (a) 23 feet by 6 feet. (c) 15 yards by 8 yards. (b) 25 inches by 7 inches. (d) 32 feet by 23 feet. (f) 21 yards by 24 yards. |