Answer:
Option D.
Explanation:
Juanito estimated that 31% of 517 is 204 is estimated wrong because
31% of 517 = 0.31 × 517 = 160.27
Now we will go through all the options.
A. 30% of 520 = 0.30 × 520 = 156
B. 40% of 520 = 0.40 × 520 = 208
C. 30% of 510 = 0.30 × 510 = 153
D. 40% of 510 = 0.40 × 510 = 204
Option D.