Answer:
686
Explanation:
Given two natural numbers with a difference of 196 have a ratio of 9:5, you want to know their sum.
Ratios
In terms of ratio units, the difference of the two numbers is 9 -5 = 4. The sum of the two numbers is 9 +5 = 14. This means the sum is 14/4 times the difference, so is ...
14/4 × 196 = 686
The sum of the two numbers is 686.
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Additional comment
The larger number is 9/4×196 = 441, the smaller number is 5/4×196 = 245.