PSLEThe graph shows the mass of a glass when empty and when different combinations of objects R, S and T are placed in the glass.
- What is the mass of the empty glass?
- What is the average mass of the objects R, S and T?
(a)
Mass of the empty glass = 150 g
(b)
Mass of R and T
= 390 - 150
= 240 g
Mass of R and S
= 380 - 150
= 230 g
Mass of S and T
= 400 - 150
= 250 g
(R + T) + (R + S) + (S + T) = 240 + 230 + 250
2 R + 2 S + 2 T = 720
2 x (R + S + T) = 720
R + S + T
= 720 ÷ 2
= 360 g
Average mass of the objects R, S and T
= 360 ÷ 3
= 120 g
Answer(s): (a) 150 g; (b) 120 g