Multi-step problems with positive and negative numbers, and checking they make sense

Answer Key - Grade 7 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. 1.

   Tala watches a whale at -2.5 m (below the surface is negative). It dives 3/4 m per second for 6 seconds, then rises 1.5 m per second for 4 seconds. Where is it now?

   -1
2. 2.

   Ari hikes from -4.5 m (lake level is 0). The trail climbs 2.5 m per minute for 6 minutes, then descends 1.25 m per minute for 8 minutes. What is the height then?

   0.5
3. 3.

   Bo's bucket of water is 14 cm deep. A leak makes the water fall 3/4 cm each hour. Now it is 5 cm deep. For how many hours has it been leaking?

   12
4. 4.

   At dawn, Esme's thermometer reads -7.5°F. The temperature rises 1.5 degrees each hour. Now it reads -1.5°F. How many hours have passed?

   4
5. 5.

   Kira's kite starts at 20 m and falls 2.5 m each minute. Now it is 7.5 m high. For how many minutes has it been falling?

   5
6. 6.

   Luz estimates (-7.2) × 4.1 as about -28, but the phone shows 29.52. What is most likely wrong with the phone's answer?

   • The answer on the screen makes sense.
   • The sign is wrong.
   • The decimal point is in the wrong place.
7. 7.

   Milo estimates 6.8 × 2.1 as about 14, but the screen shows 142.8. What is most likely wrong with the screen's answer?

   • The sign is wrong.
   • The answer on the screen makes sense.
   • The decimal point is in the wrong place.
8. 8.

   Noah estimates (-9.8) ÷ (-2.8) as about 3, but the TV game shows -3.5. What is most likely wrong with the game's answer?

   • The sign is wrong.
   • The answer on the screen makes sense.
   • The decimal point is in the wrong place.
9. 9.

   Pia estimates 5.4 × 7.9 as about 40, but the app shows 4.266. What is most likely wrong with the app's answer?

   • The sign is wrong.
   • The decimal point is in the wrong place.
   • The answer on the screen makes sense.
10. 10.

    Tala starts a hike at 12.5 m above the lake. By the end, the total change in height is -17.5 m. What does the -17.5 tell you?

    • The hiker ends 17.5 meters lower than the start.
    • The hiker is at a height of -17.5 meters.
    • The hiker did not move.
    • The hiker ends 17.5 meters higher than the start.