There are some red and green beads in a container. If 75 more green beads are put into the container, the percentage of red beads will decrease from 30% to 20%. How many red beads are in the container?

Solution

12 units ----- 7 units + 75

5 units ----- 75

1 unit ----- 75 divided by 5 = 15

Red at first

3 units ----- 3 x 15 = 45

Answer: 45 red beads

This blog is managed by Song Hock Chye, author of Improve Your Thinking Skills in Maths (P1-P3 series), which is published and distributed by EPH.

## Wednesday, September 16, 2009

### Raffles Girls Pri Sch 2007 PSLE Math Prelim Q43

Labels:
Mathematics,
Percentage

Subscribe to:
Post Comments (Atom)

## No comments:

Post a Comment