1. E: The area of the circle may be found by using the formula, A=πr2. Since the square has a diameter of 4, the circle has a radius of 2. Substituting 2 for r, into the formula above, gives A=π(2)2, or A=4π. Thus, the area of the circle is approximately 12.57 square units.
2. B: The area of the square is equal to 72, or 49, square units. The area of the circle may be represented as π(3.5)2, or 12.25π, which is approximately 38.48 square units. The area of the shaded portion of the figure equals the difference of 49 square units and 38.48 square units, or 10.52 square units.
3. C: The point represents the x-value of 3 and the y-value of -4, thus the ordered pair may be written as (3, -4).
4. C: The average may be written as (35+40+50+55)/4, which equals 45.
5. D: Since each rattle represents the delivery of 10 babies, 5 1/2 rattles represents the delivery of 55 babies.
6. E: Delivery of 85 babies would be represented by 8 whole rattles and 1/2 of another rattle, since 8 1/2 . 10=85.
7. A: The number of SUVs sold is equal to 0.13 x 23,000, or 2,990.
8. C: If 7,650 trucks are sold, which constitutes 17% of the total number of vehicles sold, then the total number of vehicles sold may be determined by solving the equation, 7650 = 0.17x. Dividing both sides of the equation by 0.17 gives 45,000.
9. B: The total number of vehicles sold may be determined by solving the following equation for x: 0.25x = 3,750. Thus, 15,000 vehicles were sold. The number of 4-door sedans is equal to the product of 0.33 and 15,000, or 4,950.
10. B: The weight increased from 8.5 pounds to 9.25 pounds, showing an increase of 0.75 pounds. The number of pounds may be converted to ounces by writing and solving the following proportion: 0.75/x=1/16. Thus, the infant gained 12 ounces during the first month of life.
11. C: The average weight may be represented as the ratio, (8.5+9.25+9.75+10.5+11+12+12.75)/7, which is approximately 10.54 pounds, or 10 pounds, 9 ounces.
12. D: The infant gained 1 pound between August and September, which was the greatest increase.
13. C: A movement of 4 units to the left and 5 units up, from the point, (10, 3) gives (6, 8), since 10 - 4 = 6 and 3 + 5 = 8.
14. A: The number of boys who attended the 1995 convention may be represented as 0.50(716), which equals 358.
15. A: In 1995, 50% of the attendees were boys and 50% were girls, thus the same number of boys and girls attended the convention.
16. A: The number of boys attending the convention, from 1995 to 1998, may be represented by the expressions, 0.50(716), 0.55(1108), 0.60(1520), and 0.35(2244). Thus, the years of 1995 and 1996 had the least number of boys in attendance, with numbers of 358 and 610, respectively.