The price of silver went from $26.20 a troy ounce down to $2…

The price of silver went from $26.20 a troy ounce down to $20.96 a troy ounce during the past 5 months.  This represents a decrease in price of what percent?  Write the rate as a percentage rounded to the nearest percent. This is a decrease in price of [d]%.  

The price of silver went from $26.40 a troy ounce down to $1…

The price of silver went from $26.40 a troy ounce down to $17.16 a troy ounce during the past 6 months.  This represents a decrease in price of what percent? Write the rate as a percentage rounded to the nearest percent. This is a decrease in price of [d]%.