Series and sigma notation, and the sum of an arithmetic series

Answer Key - Grade 11 Math Worksheet

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

1. 1.

   Kira works out 6 + 10 + 14 + … + 86 on a math club card. What is the sum?

   966
2. 2.

   Luz works out 3 + 8 + 13 + … + 93 on a math club card. What is the sum?

   912
3. 3.

   Milo works out 11 + 14 + 17 + … + 71 on a math club card. What is the sum?

   861
4. 4.

   Noah works out -9 + (-5) + (-1) + … + 63 on a math club card. What is the sum?

   513
5. 5.

   Ren works out Σ from k = 1 to 25 of (4k − 3) on the class board. What is the sum?

   1225
6. 6.

   Zee works out Σ from k = 6 to 20 of (5k − 4) on the class board. What is the sum?

   915
7. 7.

   Esme's grandparents put $15 into a savings fund in week 1, then $5 more each week than the week before. How many dollars are in the fund after 12 weeks?

   510
8. 8.

   Luz writes 4 + 9 + 14 + … + 74 in sigma notation. Which one is right?

   • Σ from k = 1 to 15 of (4k + 5)
   • Σ from k = 1 to 14 of (5k − 1)
   • Σ from k = 1 to 74 of (5k − 1)
   • Σ from k = 1 to 15 of (5k − 1)
   • Σ from k = 4 to 74 of k
9. 9.

   Milo writes 9 + 11 + 13 + … + 47 in sigma notation. Which one is right?

   • Σ from k = 1 to 47 of (2k + 7)
   • Σ from k = 1 to 20 of (9k + 2)
   • Σ from k = 1 to 19 of (2k + 7)
   • Σ from k = 1 to 20 of (2k + 7)
   • Σ from k = 9 to 47 of k
10. 10.

    Noah writes 1 + 7 + 13 + … + 67 in sigma notation. Which one is right?

    • Σ from k = 1 to 12 of (6k − 5)
    • Σ from k = 1 to 67 of k
    • Σ from k = 1 to 67 of (6k − 5)
    • Σ from k = 1 to 12 of (k + 6)
    • Σ from k = 1 to 11 of (6k − 5)