Download Racing for the Answer

Racing for the Answer
Standards Addressed
1. A2.A.APR.C.4, M3.A.APR.C.4: Rewrite rational expressions in different forms.
2. P.N.NE.A.5: Understand that rational expressions form a system analogous to the rational
numbers, closed under addition, subtraction, multiplication, and division by a nonzero rational
expression; add, subtract, multiply, and divide rational expressions.
Materials Needed
White board (or chalk board), markers (or chalk), paper & pencils, problem cards for each group.
Before conducting the activity
For each group, duplicate and cut out the set of problems. Instead you could write the
problems on index cards. Do not write the answers.
Conducting the Activity
1. Divide the class into four (or so) groups.
2. Have each group sit the same distance from the board (white or chalk).
3. The teacher hands the first student in each group the same problem card.
Directions to Students
1. The first person in each group will be given the problem card. At the signal this person will go
to the board, write the problem, then return to their seat as quickly as possible. The then hand
the marker to the next person in the group.
2. The second person hurries to the board and works the first step of the problem. After
returning to their seat the marker is passed, etc. until the problem has been solved.
3. The first correct answer scores a point for the group that found it.
4. The board is erased and the teacher hands another card to the next person in each group and
starts play again.
5. Play continues until all of the cards (or all of the time) is used up.
6. The teacher awards the group with the highest score a prize.
Variation
1. A sheet of paper with the problem could be passed from person to person in the group
(instead of on a board).
2. Use different problems and/or operations. This activity has few inherit limits—the
problems could be from grade school or calculus.
Source
This activity is based on “Racing for the Correct Answer” in the Mathematics Activities Manual
for Algebra I and II prepared by UT Martin in 1990.
Chris K. Caldwell, UT Martin, CC BY-SA 3.0
1
Cards
2
Simplify:
Simplify:
Simplify:
2m + 3
m−8
−
m2 + 7m + 6
m2 − 7m − 8
Card 14.
3
Simplify:
Simplify:
Simplify:
5
9−x
−
4
x−9
Card 19.
4
Answers — do not put on cards!
1.
2.
29
12. − 8m + 3 = −8m − 3
2m2
2m2
6x
3x + 2
13. − 4x + 3 =
4x
x +1
6.
x
x −1
14x + 3
21x2
m 2n 2
8.
15.
xx
+3
16.
−2a − 8b
15a + 30b
19.
a3
13a − 19b
9.
20
20.
4xy − x2
21.
16
4x
9
y−2
9
9−x
b2 + b + bc − c
abc
3x + 16
4x
(
1
11. −
3
3
18. −
y+1
5a2 + 4a − 2
10.
m−3
m−8
17.
m4 − n4
7.
14.
x2
−7a + 30b
4.
72
5.
4x
=− −
1
x +1
3.
−4x − 3
22.
9y2
5
1
x /∈ {2, −2, 3, −3}
undefined x ∈ {2, −2, 3, −3}