Using doubles in multiplication (java)

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Why not use Double or Float to represent currency? 14 answers

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Since you are dealing with values in a shopping cart and double 's are only precise up to a point, I would recommend that you use BigDecimal 's instead because they provide an exact representation of a number. The imprecision of doubles is what's causing your incorrect console output.

import java.math.BigDecimal;

BigDecimal dynamicRope = new BigDecimal("4"); // example value of 4
BigDecimal dynamicRopeCost = new BigDecimal("5.50"); // example value of 5.50

// Initialize the other variables as BigDecimal's here

System.out.println("Your total comes to $" +
                    dynamicRope.multiply(dynamicRopeCost)
                    .add(staticRope.multiply(staticRopeCost))
                    .add(webbing.multiply(webbingCost)));

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