Using the clues below, how many birds altogether came to the bird bath:

• There were half as many yellow finches as cardinals
• The bird bath had 4 more blue jays than sparrows
• There were 10 cardinals at the bird bath
• There were twice as many chickadees as blue jays
• There were 2 less sparrows than yellow finches

For 4th and 5th grades:  The bird bath holds 3 gallons of water.  How long will it take to fill up the bird bath with water, if the hose runs 1 quart of water every 15 seconds?