To convert the decimal 3.5 into a fraction, we start by understanding that 3.5 can be expressed as 3 plus 0.5.
The number 0.5 can be rewritten as the fraction 1/2. Hence, we can express 3.5 as:
3.5 = 3 + 0.5 = 3 + 1/2
Next, to combine these into a single fraction, we convert the whole number 3 into a fraction. Recall that any whole number can be written as itself over 1. Therefore, we rewrite 3 as:
3 = 3/1
Now, we need a common denominator to add the two fractions together. The denominator of 1 can be converted into 2 by multiplying both the numerator and denominator of 3/1 by 2:
3/1 = (3 × 2)/(1 × 2) = 6/2
Now we can add the fractions:
6/2 + 1/2 = (6 + 1)/2 = 7/2
So, the fraction representation of 3.5 is:
7/2