Mary Walker sells homemade knit scarves for $25 each at local craft shows. Her contribution margin ratio is 60%. Currently, the craft show entrance fees cost Mary $1,500 per year. The craft shows are...

Mary Walker sells homemade knit scarves for $25 each at local craft shows. Her contribution margin ratio is 60%. Currently, the craft show entrance fees cost Mary $1,500 per year. The craft shows are raising their entrance fees by 25% next year. How many
extra
 scarves will Mary have to sell next year just to pay for rising entrance fee costs?