Study the following bar graph carefully and answer the question given below.…

Percentage decrease of a quantity relative to a reference (base) value is calculated as: percentage decrease = ((base value − new value) / base value) × 100. When a question asks "the decrease in X was what percent of Y", the base for the percentage is explicitly Y, not X.

1. From the bar graph, the 1975 wheat imports = 5200 thousand tonnes and the 1976 wheat imports = 2700 thousand tonnes.

2. Decrease in imports = 1975 value − 1976 value = 5200 − 2700 = 2500 thousand tonnes.

3. Percentage decrease relative to the 1975 base = (2500 / 5200) × 100 = 48.0769...%, i.e. approximately 48.08%; the offered option, 48.07%, is the nearest match (the source answer key drops the second decimal down rather than rounding up).

Cross-check: 48.07% of 5200 = 0.4807 × 5200 ≈ 2500, which matches the computed decrease. Equivalently, the 1976 figure is (2700/5200) × 100 ≈ 51.92% of the 1975 figure, so the fall is the complement, 100% − 51.92% ≈ 48.08% ≈ 48.07%, the same result by a second route.

So the decrease in imports in 1976 is approximately 48.08% (48.07% among the offered options) of the imports in 1975.