human
Betty is saving money for a new wallet which costs $100. Betty has only half of the money she needs. Her parents decided to give her $15 for that purpose, and her grandparents twice as much as her parents. How much more money does Betty need to buy the wallet?
assistant
How much money does Betty have in the beginning? ** In the beginning, Betty has only 100 / 2 = $<<100/2=50>>50.
How much money did Betty's grandparents give her? ** Betty's grandparents gave her 15 * 2 = $<<15*2=30>>30.
How much more money does Betty need to buy the wallet? ** This means, Betty needs 100 - 50 - 30 - 15 = $<<100-50-30-15=5>>5 more.
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