Handful #20 answer

The seven tiles

S₁N₁U₂M₃G₃I₁M₃

The best three words: 57 points

1. SUMMING 29 points
2. MUSING 17 points
3. MINUS 11 points

The seven-letter word using every tile was SUMMING, which earns the 15-point length bonus on top of its tile values.

Other high scorers

SUING 11USING 11GUMS 10MUGS 10MUMS 10

There were 34 valid words of three letters or more in these tiles. A word scores the sum of its tile values plus a length bonus (4 letters +1, 5 letters +3, 6 letters +6, 7 letters +15), so one long word usually beats several short ones.