AccelePrep for the ACT Test 2nd Edition Student Text

C HAPTER 5 | H YPER P REP M ATH • 101 4. In this case, the “of” phrase is “of the maximum” and the other number is “how much oxygen the blood is carrying.” So the problem is just of maxi m carrying . If one hemoglobin molecule can carry four molecules of oxygen, 100 hemoglobin molecules can carry 400 molecules of oxygen. So %, 400 380 100 95 of maximum carrying : d n (H). 5. A percent change can be easily calculated using the “CHOOT” formula (Remember, since the answer only requires an approximation, just round the numbers to make the calculations easier): 100 Percent Change : Old Total Change Use the CHOOT formula to solve: 100 100 . , , 33 000 36 000 Population Population 2010 2000 The negative value indicates a decrease, so (E) is correct. 6. The larger the pool of people, the more with EXL: , x 50 12 1 500 x 50 12 ,1 500 ^ h , x 12 30 360 ] g ȋ ȌǤ 7. There are several routes to the correct answer, so we’ll pick one. Water ϐŽ‘™• ‹ ƒ– –Š‡ ”ƒ–‡ ‘ˆ ͳ͹ǡͷͲͲ ‰ƒŽ Ȃ ͷǡͷͲͲ ‰ƒŽ α ͳʹǡͲͲͲ ‰ƒŽŽ‘• ‡˜‡”› Ͷ Š‘—”•ǡ ƒ† ‹– ™‹ŽŽ –ƒ‡ ƒ‘–Š‡” ʹͷǡͲͲͲ Ȃ ͳ͹ǡͷͲͲ α ͹ǡͷͲͲ ‰ƒŽŽ‘• –‘ ϐ‹ŽŽ the pool completely. , gal hours , x 4 12 000 7 500 gal hours 2 hours 2 hours and 30 minutes. And 2 hours and 30 minutes after 1 p.m. is 3:30 p.m., (B). 8. A common mistake here would be to divide rather than multiply: 8 32 4 . And (F) is available as a wrong answer for this mistake. But put in the units associated with the calculation: 8 32 4 gal mi/gal mi/gal 2 In other words, a gallon-unit multiplied by a gallon-unit, just like a number, would be gallon². And mi/gal² is not a unit that answers the question “How far?” Now multiply instead: 32 8 256 gal mi gal miles, : (K). %. 100 8 : : : , 36 000 36 3 Population 2000 , , x 12 000 30 000 x 2 1