Math 397                                 Name:_________________________________________

Summer 2000

Staebler/Webster                      Exam #1 over Fractions

                                      Show ALLWORK to receive full credit!

                                      No Calculator allowed.

 

1.                  On the number line below  x  marks the position of  4/7.  Accurately mark the position of 1 2/7 on the number line.  Show work / explain how you know that the position you marked is accurate.

 

2.                  Carefully draw a picture to illustrate 2/3 + 1 1/2 using a set model.

 

3.                  Is 5/6  closer  to 3/4 or  to7/8?  Justify your answer without drawing a picture.

 

4.                  Find 8 4/9 – 5 7/9 using the indicated techniques.  Show step by step work.

A.        Exchange from the whole                      B.         Compensation

 

5.                  Use ¾ ¸ 5/7 as an example to explain WHY the following technique for the division of fractions works:  “Multiply the first fraction by the reciprocal of the second fraction.”

 

6.                  Carefully draw a picture to illustrate the calculation of 1 1/3 * 3/5 using either the “repeated addition” approach  or  the “rectangular area” approach.

 

7.                  Mrs. Jones baked a batch of cookies for a “Christmas in July” party.  Her children promptly ate 1/3 of the cookies while they were still warm.  Then her husband came home and ate 2/5 of the remaining cookies.  What fraction of the batch of cookies was left for the party?

 

8.                  Janie Jones has 15 1/2 cups of cranberries.  It takes 1 1/4 cups to make 10 inches of “cranberry chain garland”.  How many inches of “cranberry chain garland” can Janie make?

 

9.                  Mrs. Jones’ punch recipe calls for 1/3 of the punch to be grape juice and 2/5 of the punch to be cherry juice.  The remaining portion consists of ginger ale.  If she has plenty of grape juice and cherry juice, but only 2 liters of ginger ale, what is the largest amount of punch that she can make?

 

10.       Mr. Jones is preparing the family swimming pool for the “Christmas in July” party.  The directions on the chemical bag say to put 3/4 cup of the chemical into the filtering system for every cubic yard of water in the pool.  Mr. Jones estimates that the pool holds 16 2/3 cubic yards of water.  How many cups of the pool chemical should he add to the filtering system?