Adding Integers
8+(-15) = ???
8+(-15) = -7
9 - (-5) = ???
9 - (-5) = 14
10 x (-11) = ???
10 x (-11) = -110
560 / (-70) = ???
560 / (-70) = -8
Compare: -21 _____ -23
-21 __>__ -23
-9+21+(-5) = ???
-9+21+(-5) = 7
-7 - 4 - (-1) = ???
-7 - 4 - (-1) = -10
8 x (-4) x (-5) = ???
8 x (-4) x (-5) = 160
(-72) / (-3) / 4 = ???
(-72) / (-3) / 4 = 6
Order: -24, -75, 16, 35, -32, -5 from smallest to largest
-75 < -32 < -24 < -5 < 16 < 35
A football team loses 5 yards on one play and then loses 8 yards on the next play. How many yards did they lose on the two plays?
-5 + (-8) = -13 yards
In science class, Vicky did an experiment with an unknown solid. She started with 11 grams of the solid. During the experiment, the mass of the solid was decreased by 4 grams. What was the final mass of the solid?
11 - 4 = 7 grams
From sea level, a submarine descends 40 feet per minute. Where is the submarine in relation to sea level 5 minutes after it starts descending?
-40 x 5 = -200 feet
(Notice that use a negative sign to represent descending)
A town uses positive numbers to track increases in population and negative numbers to track decreases in population.
The population has decreased by 300 residents over the past 5 years. The same number of residents left each year.
What was the change in the town's population each year?
-300 / 5 = -60 residents
Compare: -96 / 6 + 8 _____ (-4) x (-5) - (-4)
-96 / 6 + 8 = -16 + 8 = -8
(-4) x (-5) - (-4) = 20 - (-4) = 24
So, -96 / 6 + 8 __<__ (-4) x (-5) - (-4)
You park in a garage 3 floors below ground level. Then you get in the elevator and go up 12 floors. What floor do you get off the elevator?
-3 + 12 = 9
You get off on the 9th floor.
You are 5 dollars in debt. You borrow 12 dollars more. What is the total amount of your debt?
5 dollars in debt can be represented by -5
-5 - 12 = -5 + (-12) = -17 dollars
The amount of your debt is 17 dollars.
A test has 20 questions. The test awards 3 points if the answer is correct and takes away 1 point if the answer is incorrect. A student answered 5 questions incorrectly. The rest of the questions were correct. How many points did the student get in the end?
3 x 15 + (-1) x 5 = 40 points
Elisa withdrew $20 at a time from her bank account and withdrew a total of $140.
Francis withdrew $45 at a time from his bank account and withdrew a total of $270.
Who made the greater number of withdrawals? Justify your answer.
Elisa: $140 / $20 = 7 withdrawals
Francis: $270 / $45 = 6 withdrawals
So, Elisa made the greater number of withdrawals.
Four friends went scuba diving today. Ali dove 70 feet, Tim went down 50 feet, Carl dove 65 feet, and Brenda reached 48 feet below sea level. Write the 4 friends' names in order from the person whose depth was closest to the surface to the person whose depth was the farthest from the surface.
Brenda (-48 feet), Tim (-50 feet), Carl (-65 feet), Ali (-70 feet)
A local bookstore has 30 copies of a bestseller when it opens on Monday morning. On Monday, it sells 6 copies of the book. On Tuesday, it sells 3 copies. On Wednesday, it receives a shipment containing 24 copies of the books and also sells 8 copies. How many books does the store have at the end of Wednesday?
30 + (-6) + (-3) + 24 + (-8) = 37 copies of the book
Denali is one of the coldest mountains on earth. The temperature is 2 degrees Celsius today and each day, it is dropping by 3 degrees Celsius.
What will the temperature of Denali be after 5 days?
2 - 3 - 3 - 3 - 3 - 3 = -13 degrees Celsius
The sign of the product of two integers with the same sign is positive. What is the sign of the product of three integers with the same sign? Explain your thinking.
(You need to answer all possible situations to get 500 points.)
The sign of the product of three positive integers is positive. (Example: 3 x 4 x 5 = 60)
The sign of the product of three negative integers is negative. (Example: -3 x (-4) x (-5) = 12 x (-5) = -60)
At 7 p.m. last night, the temperature was 10 degrees Celsius. At 6 a.m. the next morning, the temperature was -3 degrees Celsius. The temperature changed by a steady amount overnight. By how much did it change each hour? Round to the nearest tenth.
-3 - (10) = -13 degrees in 11 hours
-13 / 11 = -1.2 degrees Celsius
Ted is comparing the temperatures of three days in January. The temperatures on Monday and Tuesday were opposites. The temperature on Wednesday was neither positive nor negative. The temperature dropped below zero on Monday. Write the 3 days in order from the highest to the lowest temperature.
Tuesday (above zero), Wednesday (zero degree), Monday (below zero)