



 
Hi Priscila, You need a common denominator which is some number divisible by 10, 3, 5 and 8. In fact it's most efficient if you find the least such number. I would start by factoring each of the denominators into primes.
Now build the common denominator from the primes you have found, 2, 3 and 5. If the common denominator is to be divisible by 10 it must have a 2 and a 5 as prime factors so I begin my construction of this number as
It must also be divisible by 3 so it needs a three. Hence I continue by
The next denominator is 5 but 2 × 5 × 3 is already divisible by 5 so I can move to the last denominator,8. To be divisible by 8 the common denominator must contain three twos. It already has one two so it needs two more. Hence my common denominator is
Can you complete the problem now? Write back if you need more help,  


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