JAMB 1986 · UME · Q5

Find the reciprocal of $\dfrac{2/3}{\frac12 + \frac13}$ .

Worked solution (try it first)

Bottom: the LCD of 2 and 3 is 6, so $\frac12 + \frac13 = \frac36 + \frac26$
$= \frac56$ .
Divide by flipping the second fraction: $\frac23 \div \frac56 = \frac23 \times \frac65$
$= \frac45$ .
The reciprocal turns it upside down: $\frac54$ , option B.