I make this assumption because I know that is what Excel does. To get this answer I assume that the lambs are weighed to a precision of one decimal place, and the numbers under the graph are the inclusive upper bounds for the area above. I suspect the desired answer is one out of 32.
The labelling of the horizontal axis renders this question unanswerable. The first question asks: “What proportion of the lambs weighs less than 1.25 kg?” The results are shown on the histogram above.”
She records the weights of 32 lambs born on her farm. The introduction says: “Ali has a farm in Southland.