Take another look at the sentence:
Floating into the sky dotted with clouds, Grandma Ruth watched the birthday
balloons escape her fingers.
Floating into the sky dotted with clouds, a participle phrase, is right next to Grandma Ruth, an illogical target. The balloons, not poor Grandma, have left the ground! Before you continue, review the rules for misplaced and dangling modifiers.
Go back to the sentence to try again.