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. 3. A square has 4 right angles. 4. An oblong has 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 10. A rectangular surface 8 feet by 8 feet is a area is square feet; its perimeter is ft. ; its feet. -; its 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. much in 12 days as he can earn in 8 days. If he can earn $20 in 8 days, in 12 days he can earn (k) If a man can earn $73 in 8 months, how many dollars can he earn in 12 months? 12. If 8 lb. of sugar are worth 504, 12 lb. are worth cents. (1) If 8 tons of coal are worth $34.20, how much are 12 tons worth? (m) If 12 barrels of apples are worth $27.60, how much are 8 barrels worth? 15. Helen bought a piece of flannel that was 40 inches long; by washing it shrank 10% in length; after washing it was inches long. 16. Before washing, a piece of flannel was 40 inches in length; after washing it was 35 inches long; it shrank by washing per cent.* 17. A dealer had 25 bu. of apples; he lost 20% of them by decay; there remained bushels. (a) A dealer had 2375 bu. of apples; he lost 20% of them by decay. How many bushels remained? * It shrank what part of its original length? |