You are provided with an arithmetic question. Your task is to compute the solution using the given arithmetic operations. The only arithmetic operators needed to answer the questions are'+'(addition) and'-'(subtraction). The answer should be correct to one decimal place.

A restaurant made 9 hamburgers to serve during lunch. Only 3 wereactually served. How many hamburgers were over from lunch?
6.0

There were 2 red orchids and 4 white orchids in the vase. Jessica cutsome red orchids from her flower garden. There are now 18 redorchids in the vase. How many red orchids did she cut?
16.0

Nancy grew 2 onions, Dan grew 9 onions, and Mike grew 4 onions.They worked for 6 days on the farm. How many onions did they growin total?
15.0