Problems of the day Week 4 (Sept. 24 – Sept. 28)

Problems of the Day (Day 1) The record high in Georgia was 112 degrees Farenheit in August of 1983. The record low is -17 degrees Farenheit in 1940. What is the difference in these two temperatures? Solve 1. 4 + ( -9 ) = 2. -4 + -9 = 3. -4 - 9 = 4. -4 – ( -9 ) = 5. -36/4 = 6. -8 ( -7 ) = 2 + ( -5 ) – 3 = 4 – ( -1 ) + 8 =

Multiplying Multiple Integers When multiplying multiple integers, if there are an even number of negative signs in the problem, the answer will be positive. If there are an odd number of negative signs, the answer will be negative. Example 1: -5 ( 3 )( 2 ) In this problem, there is only one negative sign which means there is an odd number of negatives. Therefore, the answer will be negative. The answer is -30. Example 2: (-2 )( 2 )( -2 )( 2 ) In this problem, there are two negatives signs which means there are an even number of negatives. Therefore, the answer will be positive. The answer is 16. Comprehension Check 1. ( 4 )( -3 )( -2 )( -1 ) = 2. ( -1 )( -1 )( -1 )( -1 ) = 3. 6 ( -12 )( 2 ) =

Problems of the Day (Day 2 ) The temperature in Cook, Minnesota is three times colder than the temperature in Madison, Wisconsin while it is 47 degrees Farenheit in Atlanta, Georgia. If it was -11 degrees Farenheit in Madison, How much colder was it in Cook than in Atlanta? A. 14 b. 36 c. 58 d. 80 3 – 7 = 4 – ( -2 ) = 2 + ( -8 ) = -6 + -3 = 6 ( -7 ) = -56/-8 = -6 – 9 + 7 = -4 – ( -9 ) – 8 =

Problems of the Day ( Day 3 ) The star of the seventh grade football team ran with the ball 8 times. The results for his plays were +11 yds., 15 yds., 10 yds., -2 yds., -6 yds., -4 yds., 6 yds., and -8 yds. What was the mean yardage for the game? A. 2 ¾ yds. B. 7 ¾ yds. C. 22yds. d. 62 yds. Solve 8 ( -9 ) = 2. -3 ( -4 )( 5 ) = ( - 9 )( -6 ) = 4. -2 ( -7 )( -3 ) = -108/3 = 6. -224/-4 = 7. 81/-3 + 10 = 8. -114/-6 – 12 =

Applying Integer Operations Word Problems One month Owen made 3 withdrawals from $20 and one withdrawal for $60 from his account. Write and evaluate an expression that shows the change to his account. Shanna took a test with 50 questions. She lost 2 points for each of the 5 questions she got wrong. She got all 3 extra credit questions correct and received 5 points for each one. Write and evaluate an expression to show what Shanna lost or gained overall. Rita and Benne both play the same online game. In today’s play, Rita earns 6 points three times and losses 4 points twice. Bennie gets a bonus of 15 points for answering a trivia question correctly and losses 25 points twice for giving wrong answers. Who lost the most points? Dennis lost 6 points four times playing a video game. He then lost an additional 25 points. Write and evaluate an expression to show the change in Dennis’s score. Now Try questions on pg. 52 of your text.

Applying Integer Operations Word Problems A submarine cruised below the surface of the water. During a training exercise, it made 4 dives, each time descending 45 feet more. Then it rose 112 feet. What is the change in the submarine’s position? The Gazelle football team made 5 plays in a row where they gained 3 yards on each play. Then they had 2 plays in a row where they lost 12 yards on each play. What is the total change in their position? On Saturday, Mrs. Armour bought 7 pairs of socks for $3 each, and a sweater for her dog for $12. Then she found a $5 bill on the sidewalk. Over the course of Saturday, what was the change in the amount of money Mrs. Armour had? 4. The low temperature for 5 days was -5 degrees, -7 degrees, -2 degrees, 2 degrees, and -3 degrees. What was the average low temperature for those days?

Answer Key Day 1 Day 2 Day 3 112 – ( -17) = 129 degrees 3( -11 ) = -33 The sum = 22/8 = 2 3/4 47 – ( -33 ) = 80 -5 1. -4 1. -72 -13 2. 6 2. 60 -13 3. -6 3. 54 5 4. -9 4. -42 -9 5. -42 5. -36 56 6. 7 6. 56 -6 7. -8 7. -17 13 8. -3 8. 7

Applying Integer Operations Answer key (Slide 6) 3 ( -20 ) – 60 -60 – 60 or -60 + -60 = -$120 Owen’s account decreased by $120. -2 ( 5 ) + 3 ( 5 ) -10 + 15 = 5 Shanna gained 5 points. Rita Bennie 6( 3 ) – 4( 2 ) 15 +2( -25 ) 18 – 8 or 18 + ( -8 ) = 10 15 – 50 or 15 + ( -50 ) = -35 Bennie lost the most points. -6( 4 ) – 25 -24 – 25 or -24 + ( -25 ) = -49 Dennis lost a total of 49 points in the game.

Applying Integer Operations Answer Key ( Slide 7) 1. -4( 45 ) + 112 -180 + 112 = -68 The submarine was 68 ft. below sea level. 5( 3 ) + 2( -12 ) 15 – 24 = -9 The team lost 9 yards. -7( 3 ) – 12 + 5 -21 – 12 + 5 or -21 + ( -12 ) + 5 -33 + 5 = -28 Mrs. Armour will have $28 less than what she originally had. 4. When we find the average we first find the sum and then divide it by the # of integers in the problem. -5 + ( -7 ) + ( -2 ) + 2 + ( -3 ) = -15 -15/5 = -3 degrees