Question

The estimated insurance loss from a hurricane was ​$24.6 billion. This was ​$9.7 billion more than the loss from a tsunami three years later. What was the estimated insurance loss from the​ tsunami?

Answer 1

In billions, ...
  tsunami + 9.7 = 24.6
  tsunami = 24.6 -9.7 = 14.9

The estimated insurance loss from the tsunami was $14.9 billion.