PSLEThe graph shows the mass of a glass when empty and when different combinations of objects B, C and D are placed in the glass.
- What is the mass of the empty glass?
- What is the average mass of the objects B, C and D?
(a)
Mass of the empty glass = 170 g
(b)
Mass of B and D
= 490 - 170
= 320 g
Mass of B and C
= 420 - 170
= 250 g
Mass of C and D
= 500 - 170
= 330 g
(B + D) + (B + C) + (C + D) = 320 + 250 + 330
2 B + 2 C + 2 D = 900
2 x (B + C + D) = 900
B + C + D
= 900 ÷ 2
= 450 g
Average mass of the objects B, C and D
= 450 ÷ 3
= 150 g
Answer(s): (a) 170 g; (b) 150 g