Answer:
3,131,313
Step-by-step explanation:
Let X represent the number of cases with diabetes in 1973.
An increase of 396% in diabetes cases in 1973 would be;
12.4 million = 396/100 × X
12.4 million = 396X/100
Cross multiply
12.4 million × 100 = 396X
X = [(12.4 million × 100) / 396]
X = 3,131,313
Therefore, the number of diabetes cases in 1973 is 3,131,313 cases