D125 - Mathematics for Elementary Educators II

D125 - Mathematics for Elementary Educators II Find the slope of the line through the pair of points by using the slope formula 1, -2 and 3, 4 - ANSWER subtract -2 from 4 = -6 and subtract 1 from 3 = 2. Then reduce from 6 over 2 to 3. So the answer is 3 Write the following equation in slope intercept from and identify the slope and y intercept. 4x+5y=20 - ANSWER The equation is y=-4 over 5x+4 The slope of the line is -4 over 5 The y intercept of the line is (0,4) 65 men and 55 women are enrolled in calculus. There are 20 business majors, 50 biology majors, 35 computer science majors, and 15 mathematics majors. No person has a double major. If a single calculus student is chosen, find the following probabilities - ANSWER 65 over 120 = 13 over 24. The probability that the student is a business major is 20 so 20 over 120 or 1/6. There are 15 mathematics majors enrolled in calculus, so the probability of selecting a mathematics major is 15 Over 120. The probability of selecting a non mathematics major is 105 over 120 0r 7/8. Since there are no double majors, majoring in business and majoring in mathematics are mutually exclusive events. The probability of selecting either a business major or a mathematics major is represented as P(business union∪mathematics). 20 + 15 over 120 = 7/24. Remember to use calculator to reduce! When a particular type of thumbtack is dropped, it will land point up (A flat-top thumbtack resting on its flat top) or point down (A flat-top thumbtack resting on the edge of its flat top and the tip of its needle). This experiment was repeated 100 times with the following results: point up: 58 times; point down: 42 times. a. What is the experimental probability that a particular type of thumbtack will land point up? b. What is the experimental probability that a particular type of thumbtack will land point down? c. If the experiment was tried another 100100 times would the same results occur? Why? d. Is it expected that nearly the same results occur on a second trial? Why - ANSWER Point up and point down are just the number over 100. If the experiment was tried another 100 times would the same results occur? NO Is it expected that nearly the same results will occur on a second trial: YES In the game of "Between," two cards are dealt from a standard deck and not replaced. You then pick a third card from the deck. To win, you must pick a card that has a value between the other two cards. The order of values is 2, 3, 4, 5, 6, 7, 8, 9, 10, J, Q, K, A, where the letters represent a jack, queen, king, and ace, respectively. Determine the probability of your winning if the first two cards dealt are a 7 and a queen. - ANSWER between 7 and a queen there are 4 spots. so 4 x 4(suites for each value) = 16. There are 52 cards and 2 have been taken out so 16 over 50 is 8/25. A Executive committee consists of 12 members 4 men and 8 women, 3 members are slected at randome to attend a meeting, what is the probability that all 3 selected are women? - ANSWER 8/12 x 7/11 x 6/10 = 336/1320 = 14/55 So just decrease the numbers by the amount drew from the hat and time it by themselves. Multiplicative Inverse of 1 1/4 is: - ANSWER When you do the math on the calculator it come out to 5/4 to inverse it you just flip it so it = 4/5 Multiplication principal 4/5x = -4/3 so x= - ANSWER Divide both sides by 4/5 and the calculator will show -3/5 to get the principal you flip it so = -5/3 Perform the proper calculations 16x3 1/4 = - ANSWER change 3 1/4 to improper fraction and divide 16/1 divided by 13/4 = 52 Metro train had a route reduction of 1/10 of its routes. 198 routes were left after the reduction, how many routes were there originally? - ANSWER Take 198 dived by what was left 9 = 22 add that to 198 = 220 11 times some number minus 4/21 is equal to 10 times the same number plus 3/14 - ANSWER simplify by writing 4/21 as an equivalent fraction to 8/42 and 3/14 is equivalent to 9/42 thus x = 17/42 Sporting goods store making soccer shorts they have 8 8/9 yd fabric to make them. Each pair requires 5/4 yd of fabric - ANSWER how many shorts can be made? 7 how much will be left over: Divide 1/9 that is left over by the 5/4 material it takes to make it = 5/36 A local government had an employee reduction and lost 2/3 of its employees. If 44 of its employees were left after the reduction how many employees were there orginally? - ANSWER 44 x 3 = 132 originally 7^9 x 7^7 = - ANSWER just add the powers not the number = 7^16 684.33 Rounded - ANSWER 684.33 rounded to the nearest hundred 700 Tenth = 684.3 Unit = 684 Ten = 680 Thousand = 1000 Hundredths = 684.30 Left is Ands Right is Enths 17 over 2^2x55 is this a terminating decimal - ANSWER No because 17 does not go into 5 or 2 Nathan received a 5% raise last year, if his salary is now $17,535 what was his salary last year? - ANSWER 100% + 5% = 105% Divide 17535 by 1.05 = 16700 There are 140 coins in a piggy bank of which 40% are dimes. what is the least possible amount of money that could be in the piggy bank? - ANSWER 140 x 40% = 56 (5.60 in dimes) subtract 56 from 140 = 84 the least is .84 cents so add 5.60 + .84 = $6.44 67.5 is _________% of 22.5 - ANSWER 300%