Friday, December 15, 2006

Justin's Percentage Growing Post

Question 5:

The principal announced that 50% of the children in Ms. Stanzi's class met their reading goal for the month and that 55% of the children in Ms Lowrey's class met their reading goal for the month. Ms Stanzi said that a greater number of her students met their reading goal. Could Ms Stanzi be correct? Why or Why not.

Ms. Stanzi: Ms. Lowrey:

40/2=20 40/1.5=26.66

No, she can't be correct because there is more of an average of students that are meeting their reading goal and the only way Ms. Stanzi could be correct is if a bigger number of kids start improving their reading.

Question 6:
Use a hundred grid (unit square) to illustrate the following questions. Once you have explained and illustrated what the question means solve it.
a) 16 is 40% of what number?
b) What is 120% of 30?

a) 40% of 100 is 40
40/100=0.4
16 x 0.4=40
40/100 = 16/40

I got this answer by first dividing 40 by 100 and that gives me 0.4.So then you multiply the decimal by the part and that gives you 40% of 16.

b) 120% of 100 is 120
120/100=1.2
30 x 1.2=36

120/100 = 36/30

I got this answer by first finding out what 120% of 100 is which is 120. So then I divided 120 by 100 which gives me 1.2. Then you multiply by the whole which is 30 by 1.2, and that gives you 36 out of 30.