PSLEThe graph shows the mass of a glass when empty and when different combinations of objects X, Y and Z are placed in the glass.
- What is the mass of the empty glass?
- What is the average mass of the objects X, Y and Z?
(a)
Mass of the empty glass = 140 g
(b)
Mass of X and Z
= 420 - 140
= 280 g
Mass of X and Y
= 370 - 140
= 230 g
Mass of Y and Z
= 410 - 140
= 270 g
(X + Z) + (X + Y) + (Y + Z) = 280 + 230 + 270
2 X + 2 Y + 2 Z = 780
2 x (X + Y + Z) = 780
X + Y + Z
= 780 ÷ 2
= 390 g
Average mass of the objects X, Y and Z
= 390 ÷ 3
= 130 g
Answer(s): (a) 140 g; (b) 130 g