Answer:
The number of double dip sundae that can be created with 1 topping is:
825
Explanation:
Since, there are 10 different flavors and same flavor can be used for both the dips.
Also, there are a total of 15 different toppings.
Hence, the number of different double dip sundae that can be created with 1 topping is:
825
( Since, the order in which the two sundae are placed does not matter. Hence, we need to use the method of combination.
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As
denotes the number of ways of choosing of 2 different toppings from the 10 flavors and the addition 10 term represent the 10 cases case in which both the dips are of same flavor
Hence,
)