Friday, August 31, 2012

Sec1 Pythagoras Theorem (Fr Alexia)

A creeper plant is climbing up and around a cylindrical tree trunk in a helical manner. The tree trunk has a height of 540 inches and a circumference of 48 inches.
If the creeper covers a vertical distance of 90 inches in one complete twist around the tree trunk, what is the total length of the creeper?

Click here for my solution

Monday, August 13, 2012

Friday, August 3, 2012

P6 percentage (double meaning?)


Is this question ambiguous?
Depending on how you read the question (ie. where you pause during your reading), you will get a different interpretation of the question.

Meaning1: (The intended meaning, ie. no pause after "$2380") 
"... buy a wardrobe, which cost $2380 after a 20% discount."
80% --> $2380
(a) Amount saved at fair (20%) --> $2380 / 4 = $595


Meaning2:
"... buy a wardrobe, which cost $2380, after a 20% discount."
100% --> $2380
(a) Amount saved at fair --> 20% x $2380 = $476