One way to solve 4x1/2 is with pictures.
Another way to solve 4x1/2 is to multiply both denominators and numerators.
How to Multiply a Fraction by a Fraction
The first step to multiply a fraction by a fraction is to multiply the first fraction's numerator with the second fraction's numerator. Next, you have to multiply the first fraction's denominator with the second fraction's denominator. Finally, to get your answer, you take the answers from the numerator multiplied by the other numerator question and the denominator multiplied by the other denominator and make a fraction of the answers (Simplify if possible).
How to Multiply a Fraction by a Mixed Fraction
The first thing I did to multiply a fraction by a mixed number is to convert the mixed number to an improper fraction by multiplying the whole number by the denominator. Then you take that answer and add te numerator. Next you make that answer a fraction by just taking the denominator and adding the last answer on top of it. After that you multiply the numerator with the improper numerator and multiply the denominator with the improper fraction's denominator. Finally, you convert the improper fraction into a mixed fraction by counting how many times the denominator fits into numerator and make the remainder into a fraction(Simplify the fraction if possible).
How to Multiply a Mixed Fraction by a Mixed Fraction
The first step you're supposed to do when you are multiplying a mixed fraction with a mixed fraction is to make both of the mixed fractions into improper fractions. Then you multiply the numerators and the denominators. Next, you get the answer's numerator and denominator and you find out how many times the denominator fits into the numerator. After that, you make the remainder into a fraction (Simplify if possible). That is how you multiply two mixed fractions.