Work out a tip in your head
Move the decimal point once, then double it or add half.
- Find 10% by moving the decimal one place left: $47.60 → $4.76. Round to $4.80.
- For 20%, double it: $9.60.
- For 15%, add half of the 10%: $4.80 + $2.40 = $7.20.
Try it now: What's 15% and 20% of $63? ($9.45 and $12.60.)
Next crumbs
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