SAT Test Prep Lesson 2 Math Source

SAT Test Prep Lesson #2 – Math Source: AVID Coordinator’s Training on February 6, 2014 by Study Smart Tutors http: //studysmarttutors. com/

“To succeed, we must first believe that we can. ” -Michael Korda

Plugging In • Questions often have variables (x, y, a, b). Many times, answer choices also have variables. Whenever there are variables in the question and in the answer, plug in your answer own number.

Plugging In – The Steps 1. Indentify the variables and replace them with specific numbers (but not 0 or 1) 2. Solve the problem using your selected numbers (different numbers for each variable) 3. Write down the answer you find and label it as “TARGET” 4. Plug your numbers into each answer choice to match the “TARGET” 5. If more than one answer matches, pick new numbers and try again

Plugging In – Example If a store sells a shirt for h dollars, how much would that shirt cost if it was marked down by q%? a. b. c. d. e. hq ¼ (hq) h(1 -(q/100)) q(1 -(h/100)) 2 hq 1. 2. 3. 4. Let h = $100 If a $100 shirt is marked down 10%, it costs: 100 – (. 1)(100) The answer, or TARGET is $90 Plug in $100 and 10% into answer choices until you get $90

Plugging In – Practice #1 1. If w hats cost z dollars, how many hats could you buy with $100? a. b. c. d. e. 100/w 100 wz 100 w/z 100 z/w wz 1. 2. 3. 4. Let w = 5; let z = 10 If w=5 and z=10 then each hat costs $2 Now You Try On Your Own The answer, or TARGET is $50 Plug in 100(5)/10 = 50

Plugging In – Practice #2 2. If the sum of three consecutive odd integers is P, then in terms of P, what is the greatest of the three integers? a. b. c. d. e. (P-6)/3 (P-3)/3 (P+3)/3 (P+6)/3 1. 2. 3. 4. Let the three integers be 1, 3, and 5 Now You Try 1 3 + Own There sum is On+Your 5 = 9 The answer, or TARGET is $5 Plug in (9+6)/3=5

Working Backwards • Rather than plugging in your own numbers, plug in the numbers they provide. You should plug in numbers when there are variables in the question, numbers in the answers choices, and the question ASKS FOR A SPECIFIC AMOUNT

Working Backwards– The Steps 1. Label the answer choices so you know what they stand for 2. Start by trying the middle answer (usually “C”) 3. Look for something in the problem that is proven true 4. If you found one answer that works, you’re done

Working Backwards – Example Marc is half as old as Tony and three times as old as Ben. If the sum of their ages is 40, how old is Marc? a. b. c. d. e. 3 6 12 18 24 1. 2. 3. 4. The answers show Marc’s age Marc + Tony + Ben = 40 Start with answer C. So if Marc is 12, Tony is 24, and Ben is 4. 12 + 24 + 4 = 40 It works. You’re done!

Working Backwards – Practice #1 1. Chef Emeril has equal amounts flour, sugar, and salt. He made pretzels by mixing 1/3 of the flour, ½ of the sugar, and ¼ of the salt. If he made 52 lbs of pretzels, how many pounds of sugar did he have to start? a. b. c. d. e. 45 48 50 52 56 Now You Try On Your Own

Use Logic Now You Try On Your Own

Additional Practice With the remaining class time, click on the SAT logo below to view videos of sample math questions.