Direct, inverse, joint and combined variation

Answer Key - Grade 11 Math Worksheet - Building Confidence

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

1. 1.

   Ari writes y = kx² on a worksheet. When x = 4, y = 48. What is k?

   3
2. 2.

   Esme writes y = kx² in pencil. When x = 5, y = 100. What is k?

   4
3. 3.

   Jun writes y = k/x² in a math book. When x = 2, y = 7. What is k?

   28
4. 4.

   Milo writes y = kxz in a notebook. When x = 2 and z = 7, y = 42. What is k?

   3
5. 5.

   Noah writes y = kxz in pencil. When x = 5 and z = 3, y = 90. What is k?

   6
6. 6.

   Pia writes y = kxz in a math book. When x = 4 and z = 3, y = 18. What is k?

   3/2
7. 7.

   x = 3, 4, 6; y = 12, 9, 6. Ren records a table of x and y on a worksheet. Which equation fits every row?

   • y = x + 9
   • y = 4x
   • y = 36/x
8. 8.

   x = 3, 6, 9; y = 2, 4, 6. Tala records a table of x and y in a notebook. Which equation fits every row?

   • y = 6/x
   • y = (2/3)x
   • y = x − 1
9. 9.

   x = 1, 3, 5; y = 15, 5, 3. Ari records a table of x and y in pencil. Which equation fits every row?

   • y = x + 14
   • y = 15x
   • y = 15/x
10. 10.

    x = 4, 6, 10; y = 10, 15, 25. Bo records a table of x and y in a math book. Which equation fits every row?

    • y = 40/x
    • y = x + 6
    • y = (5/2)x