Write an equation for a story, and a story for an equation

Answer Key - Grade 8 Math Worksheet - Building Confidence

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

1. 1.

   Ari's bean plant is 5 cm and grows 3 cm a week; the pea plant is 11 cm and grows 1 cm a week. Which equation shows when they match after w weeks?

   • 3w + w = 5 + 11
   • 3w + 5 = w + 11
   • 3w + 11 = w + 5
   • 5w + 3 = 11w + 1
2. 2.

   Bo is on page 20 of a comic, reading 15 pages a day, and on page 60 of a novel, reading 5 a day. Which equation tells when the page numbers match after d days?

   • 15d + 5d = 20 + 60
   • 15d + 60 = 5d + 20
   • 15d + 20 = 5d + 60
   • 20d + 15 = 60d + 5
3. 3.

   Jun's sunflower is 8 cm and grows 5 cm a week; the bean plant is 20 cm and grows 2 cm a week. Which equation tells when they are equal after w weeks?

   • 5w + 2w = 8 + 20
   • 5w + 8 = 2w + 20
   • 8w + 5 = 20w + 2
   • 5w + 20 = 2w + 8
4. 4.

   Luz's sticker book has 10 stickers and gains 7 a day; the card box has 34 cards and gains 3 a day. After how many days do they match?

   6
5. 5.

   Milo's red kite is at 4 m and climbs 5 m a minute; the blue kite is at 18 m and climbs 3 m a minute. After how many minutes are they level?

   7
6. 6.

   Noah's bean plant is 1 cm and grows 8 cm a week; the pea plant is 26 cm and grows 3 cm a week. After how many weeks are they equal?

   5
7. 7.

   Pia's bean plant starts at 5 cm and grows 3 cm a week. Solving 3w + 5 = w + 13 gives w = 4. How tall is each plant then, in cm?

   17
8. 8.

   Ren builds two block towers. One starts at 6 blocks and gains 5 a day; solving 5d + 6 = 2d + 18 gives d = 4. How many blocks tall is each tower then?

   26
9. 9.

   Tala's red kite starts at 9 m and climbs 4 m a minute. Solving 4x + 9 = x + 24 gives x = 5. How high is each kite then, in m?

   29
10. 10.

    Zee's sunflower starts at 2 cm and grows 6 cm a week. Solving 6w + 2 = 2w + 22 gives w = 5. How tall is each plant then, in cm?

    32