Desk Calculator, Basic Office Calculator with 12 Digits Large Display, Dual S...

[MU]: Mark-up and Mark-down. Example: Enter [4+32], [MU], then get the result of [(4+32)/32] 100. Enter [90-80], [MU], then get the result of [(90-80)/80] 100. Enter [80 10], [MU], then get the result of 80 (100+10)%/100%.

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