CCommunity
Logic: Here, 4 is added to the numerator of the fraction.
2.25 : 13/4
$(2.25 = \frac{{225}}{{100}} = \frac{9}{4} \to \;4 + \frac{9}{4}\; = \;\frac{{13}}{4})$
Similarly,
3.75 : ?
$(3.75 = \frac{{375}}{{100}} = \frac{{15}}{4} \to \;4 + \frac{{15}}{4}\; = \;\frac{{19}}{4})$
Hence, the answer is 19/4.