



 
We have two responses for you. Hi Raymond, What you are working with here is what is called equivalent fractions, meaning the second fraction is just a multiple of the first. In order to solve the question, you need to first ask yourself what operation was done to the 8 to change it to 16. Once you have this answer, you can then perform the same operation to the 5 to find the question mark. For example, if I have the following question: I first ask myself, what operation was done to the 7 to change it to 28. Obviously, 7 is multiplied by 4 to become 28. Knowing this, we simply multiply 3 by 4, which gives us 12. This is now replaced for the question mark. Sara Hi Raymond,
We can see that 2 must have been multiplied by 4 in order to get 8 (4*2=8) by dividing 8 by 2 (8/2=4). So we must multiply the numerator by the same number in order to have an equivalent fraction.
Because 4/4 is really 1, we aren't really changing the value, just the way we write it.  


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