SOLUTION: johnny has a postcard collection 1/2 are from canada 1/4 are from japan 1/8 from france 1/6 from mexico 4 are from italy How many postcards does johnny have altogether

The fractions you gave will not yield a solution because they
add to more than 1 whole set of post cards by themselves. Perhaps
you mis-typed one of them. So I substituted some other fractions that 
will give an answer:

1/2 are from Canada
1/5 are from Japan
1/7 from France
1/10 from Mexico
4 are from Italy

Let N = the number of postcards altogether


The LCD of all those denominators is 70 so we multiply every term by 




Then you will not have any fractions when you multiply all those



Combine all the like terms on the left:



Subtracting  from both sides:



Dividing both sides by 4



So you have 70 post cards.

Edwin