WAEC 2020 · Paper 2 · Q8

(a)
Ms. Maureen spent $\frac14$ of her monthly income at a shopping mall, $\frac13$ at an open market and $\frac25$ of the remaining amount at a mechanic workshop. If she had ₦225,000.00 left, find: (i) her monthly income; (ii) the amount spent at the open market.
Separate values with commas, e.g. 3, −2
(b)
The third term of an Arithmetic Progression (A.P.) is $4m - 2n$ . If the ninth term of the progression is $2m - 8n$ , find the common difference in terms of $m$ and $n$ .

Worked solution (try it first)

The mall and market take $\frac14 + \frac13 = \frac{7}{12}$ of her income, leaving $\frac{5}{12}$ .
The workshop takes $\frac25$ of that remainder: $\frac25 \times \frac{5}{12} = \frac16$ .
What's left is $\frac{5}{12} - \frac16 = \frac14$ of her income.

$\frac14$ of her income is ₦225,000, so her income is $4 \times 225\,000 = ₦900,000$ .