Answer:
[tex]Question \: 1: \: let \: the \: question \: mark \: be \: n \\ n = 63 \\
Question \: 2: \: the \: error \: the \: student \: made \: is \: \\ 4x + 40 = 6x - 10 \: insteade \: of : \\ 4x + 40 + 6x - 10 = 180. \\
Question \: 3: \: x = 15 \\
Question \: 4: m( GFC)
= 80. \\ [/tex]
Step-by-step explanation:
[tex]let \: the \: unknown \: be \: n \\ then \\ 87 + n = 150 \\ n \: = 150 - 87 = 63. \\ the \: mistake \: is \: by \: the \: expression : \\ 4x + 40 = 6x - 10 \: insteade \: of : \\ 4x + 40 + 6x - 10 = 180. \\ 10x = 150 \\ x = 15. \\ 6x - 10 = 6 \times 15 - 10 \\ GFC
= 80. \\ [/tex]