Draw a line that fits the dots

Grade 8 Math Worksheet

Circle the best answer.

1. 1.

   Ren plotted minutes of study against quiz scores for eight classmates. Four ruler lines are drawn. Which line fits the dots best?

   • Line D, through (20, 65) and (50, 73)
   • Line C, through (20, 65) and (90, 93)
   • Line A, through (20, 74) and (90, 78)
   • Line B, through (20, 62) and (90, 91.5)
2. 2.

   Tala's class measured arm spans and heights. Everyone stretched out like a starfish. Which of the four ruler lines fits the dots best?

   • Line C, through (155, 156) and (160, 163)
   • Line B, through (140, 154) and (175, 165)
   • Line D, through (140, 142) and (175, 178.5)
   • Line A, through (140, 145) and (175, 180)
3. 3.

   Zee logged eight dog walks: minutes walked and blocks covered. The dog stopped to sniff everything. Which of the four ruler lines fits the dots best?

   • Line B, through (15, 13) and (50, 34)
   • Line D, through (15, 19) and (50, 25)
   • Line C, through (15, 11.5) and (50, 32.5)
   • Line A, through (15, 13) and (30, 19)
4. 4.

   Ari timed ice cube trays left in the sun and weighed the melted water. Which of the four ruler lines fits the dots best?

   • Line C, through (10, 28) and (15, 41)
   • Line A, through (5, 20.5) and (40, 91.5)
   • Line D, through (5, 24) and (40, 94)
   • Line B, through (5, 42) and (40, 66)
5. 5.

   Bo's club drew two ruler lines through the tomato plant dots. Each line has as many dots above as below. Which line fits better, and why?

   • Line B, because it passes through more dots.
   • Line A, because its dots stay closer to it.
   • Line A, because it is steeper.
   • They fit equally well, because each has as many dots above as below.
6. 6.

   Esme tried two ruler lines on the plot of a water-bottle rocket. Each has as many dots above it as below it. Which line fits better, and why?

   • Line B, because it is steeper.
   • They fit equally well, because each has as many dots above as below.
   • Line A, because it passes through more dots.
   • Line B, because its dots stay closer to it.
7. 7.

   Jun asked eight classmates about homework time and problems finished, then tried two ruler lines. Each has as many dots above as below. Which line fits better, and why?

   • Line B, because it is steeper.
   • Line A, because its dots stay closer to it.
   • Line B, because it passes through more dots.
   • They fit equally well, because each has as many dots above as below.
8. 8.

   Kira measured eight potted plants of different ages and drew two ruler lines. Each has as many dots above as below, and one plant leans toward the window. Which line fits better, and why?

   • They fit equally well, because each has as many dots above as below.
   • Line A, because it passes through more dots.
   • Line B, because its dots stay closer to it.
   • Line A, because it is steeper.
9. 9.

   Luz kept three plots about a growing puppy. For which plot is a straight fit line a good model?

   • Plot B, because its dots change steadily from left to right.
   • Plot A, because its dots stay near one straight line.
   • Plot C, because a ruler line can go through the middle of any dots.
10. 10.

    Noah's play-ball club made three plots, and one ball rolled under the bleachers. For which plot is a straight fit line a good model?

    • Plot C, because its dots stay near one straight line.
    • Plot A, because a ruler line can go through the middle of any dots.
    • Plot B, because its dots change steadily from left to right.