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Casio FX-991DE X vs Casio FX-991ES

    3.03 in
    0.44 in
    Casio FX-991DE X Calculator
    Casio FX-991DE X
      3.15 in
      0.48 in
      Casio FX-991ES Calculator
      Casio FX-991ES
      Available colors
      User rating
      65
      3.6 out of 5
      65 user ratings
      5 stars
      		24 %
      4 stars
      		30 %
      3 stars
      		30 %
      2 stars
      		9 %
      1 stars
      		4 %
      158
      3.3 out of 5
      158 user ratings
      5 stars
      		25 %
      4 stars
      		15 %
      3 stars
      		32 %
      2 stars
      		18 %
      1 stars
      		6 %

      Full Comparison

      Units:

      Technical details

      Casio FX-991DE XCasio FX-991DE X
      Casio FX-991ESCasio FX-991ES
      TypeScientific calculatorScientific calculator

      Design

      Casio FX-991DE XCasio FX-991DE X
      Casio FX-991ESCasio FX-991ES
      Colour of productBlack
      • Silver
      • White
      Control typeButtonsButtons
      Form factorPocketPocket

      Dimensions

      Casio FX-991DE XCasio FX-991DE X
      Casio FX-991ESCasio FX-991ES
      Width3.03 in3.15 in
      Height0.44 in0.48 in
      Depth6.52 in6.34 in
      Weight3.17 oz3.7 oz

      Display

      Casio FX-991DE XCasio FX-991DE X
      Casio FX-991ESCasio FX-991ES
      Number of display lines22
      Display typeLCDDot-matrix
      Display tiltingnono
      Second displaynono
      Display lightnono

      Connectivity

      Casio FX-991DE XCasio FX-991DE X
      Casio FX-991ESCasio FX-991ES
      Data transfernono

      Power

      Casio FX-991DE XCasio FX-991DE X
      Casio FX-991ESCasio FX-991ES
      Power source
      • Solar
      • Battery
      • Solar
      • Battery
      Battery operatedyesyes
      Battery typeLR44AAA
      External power connection
      • External source
      • Solar cell
      		Solar cell

      Pros & Cons

      Pros
          Cons

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              Often compared with Casio FX-991ES

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