Joan's stamp collection consists of three books. Two tenths of her stamps are on the first book, several sevenths are in the second, and there are 303 stamps in the third book. How many stamps are there in Joan's collection?

The answer is 3535. Let x = total books, y = several sevenths. The equation to solve is 2x/10 +xy/7 +303=x. Getting rid of the denominators by multiplying both sides by 35 and collecting the unknowns on one side you have 7x + 5xy-35x = -35(303). y can only be one of the following: 2,3,4,5,6,7 (since the problem says "several sevenths" you can eliminate 0,1). By process of elimination y=5 works and x=3535

"several" sevenths? What kind of nonsense is that?

Anyway if that means 5/7, then
2/10 + 5n/7 + 303 = n
n = 3535

make that 2n/10 + 5n/7 + 303 = n

To find the total number of stamps in Joan's collection, we need to determine the number of stamps in each book and then add them together.

Let's start by calculating the number of stamps in the first book. We know that two-tenths of Joan's stamps are in the first book. To find this quantity, we'll multiply the total number of stamps in her collection by the fraction representing two-tenths:

Number of stamps in the first book = (2/10) * total number of stamps

Next, we need to determine the number of stamps in the second book. We are given that several sevenths of Joan's stamps are in the second book. However, the specific number of sevenths is not provided. Therefore, without further information, it is not possible to determine the exact number of stamps in the second book. We will keep this as a variable, let's call it "x".

Number of stamps in the second book = (x/7) * total number of stamps

Finally, we are given that there are 303 stamps in the third book. So, the number of stamps in the third book is given by:

Number of stamps in the third book = 303

To find the total number of stamps in Joan's collection, we add the number of stamps in each book:

Total number of stamps = Number of stamps in the first book + Number of stamps in the second book + Number of stamps in the third book

Total number of stamps = (2/10) * total number of stamps + (x/7) * total number of stamps + 303

Unfortunately, based on the information provided, we do not have enough information to determine the exact number of stamps in Joan's collection.