1. Encik Basri's age is four times his child's age. 4 years ago, Encik Basri's age is six times his child's age. Find the age of Encik Basri's child now.
Let En Basri's age = x and his child's age = y,
x = 4y --- (1)
x - 4 = 6(y - 4) --- (2)
Substituting (1) into (2),
4y - 4 = 6y - 24
2y = 20
y = 10
En Basri's child is 10 years old now.
2. The length of rope P is three times the length of rope Q. After 10cm of rope is cut from rope P and rope Q respectively, the length of rope P is four times the length of rope Q. Calculate the origimal length, in cm, of rope P before it is cut.
Let length of rope P = p and length of rope Q = q,
p = 3q --- (1)
p - 10 = 4(q - 10) --- (2)
Substituting (1) into (2),
3q - 10 = 4q - 40
q = 30
p = 3q
= 3 x 30
= 90
The original length of rope P is 90 cm.