Step-by-step explanation: Make your denominator equal using the concept of LCM, then subtract the numerators accordingly. Rewrite each fraction to its equivilent fraction with a denominator equal to the LCM=30, then you need to subtract the numberators, but make sure to reduce your answer to the lowest possible term. I hope this helps.
<span>valid. She used a representative sample </span>because she correctly found the average and 18,000 is a reasonable number to get for a the problem
