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 = 120 g
(b)
Mass of B and D
= 450 - 120
= 330 g
Mass of B and C
= 440 - 120
= 320 g
Mass of C and D
= 490 - 120
= 370 g
(B + D) + (B + C) + (C + D) = 330 + 320 + 370
2 B + 2 C + 2 D = 1020
2 x (B + C + D) = 1020
B + C + D
= 1020 ÷ 2
= 510 g
Average mass of the objects B, C and D
= 510 ÷ 3
= 170 g
Answer(s): (a) 120 g; (b) 170 g