Related Clues:

• Toss into the mix
• Add as a bonus
• Verb used in recipes
• Gibe, with 'up'
• Keep talking
• Count up
• Factor a sum
• Figure a sum
• Way to check the check
• What summers do
• Go figure?
• Do sumthing?
• Lengthen (with ''to'')
• Perform an operation?
• Write further