Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 50% of Mary and John’s combined income?  Choose the correct answer.
A) $3,000  B) $4,000  C) $7,000  D) $11,000  E) $25,000
Let Mary's income increase by x, then the equation will be   15,000 + x= (50 /100)* (15,000 + x + 18000 )   15,000 + x = (1/2) * (33,000 + x)   30,000 + 2x = x+ 33,000   x =3,000   So, $3,000nswer will be $3,000
<result>A</result>
Mary’s annual income is $15,000 and John’s annual income is $18,000. By how much must Mary’s annual income increase so that it constitutes 50% of Mary and John’s combined income?