Answer: Adenike scored 64 marks, while Musa scored 45 marks
Step-by-step explanation: We shall start by assigning letters to each unknown variable. Let Adenike’s mark be d while Musa’s mark shall be m.
First of all, if Adenike obtained 19 marks more than Musa, then if Musa scored m, Adenike would score 19 + m (or d = 19 + m). Also if Adenike has obtained one and half her own mark (which would be 1 1/2d or 3d/2), it would have been equal to 6 times more than twice Musa’s mark (or 6 + 2m). This can be expressed as
3d/2 = 6 + 2m. So we now have a pair of simultaneous equations;
d = 19 + m ———(1)
3d/2 = 6 + 2m ———(2)
Substitute for the value of d into equation (2), if d = 19 + m
(3{19 + m})/2 = 6 + 2m
By cross multiplication we now have
3(19 + m) = 2(6 + 2m)
57 + 3m = 12 + 4m
We collect like terms and we have
57 - 12 = 4m - 3m
45 = m
We now substitute for the value of m into equation (1)
d = 19 + m
d = 19 + 45
d = 64
So Adenike scored 64 marks while Musa scored 45 marks
