diff --git a/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/BigFraction.java b/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/BigFraction.java
index cee2a6e..3962e2e 100644
--- a/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/BigFraction.java
+++ b/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/BigFraction.java
@@ -1019,7 +1019,17 @@
 
     @Override
     public int hashCode() {
-        return 37 * (37 * 17 + numerator.hashCode()) + denominator.hashCode();
+        // Incorporate the sign and absolute values of the numerator and denominator.
+        // Equivalent to
+        // Arrays.hashCode(new int[] {signum(), numerator.abs(), denominator.abs()})
+        // int hash = 1;
+        // hash = 31 * hash + signum();
+        // hash = 31 * hash + numerator.abs().hashCode();
+        // hash = 31 * hash + denominator.abs().hashCode();
+        // Note: BigInteger.hashCode() * BigInteger.signum() == BigInteger.abs().hashCode().
+        final int numS = numerator.signum();
+        final int denS = denominator.signum();
+        return 31 * (31 * (31 + numS * denS) + numerator.hashCode() * numS) + denominator.hashCode() * denS;
     }
 
     /**
diff --git a/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/Fraction.java b/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/Fraction.java
index 31e7cde..be85fb3 100644
--- a/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/Fraction.java
+++ b/commons-numbers-fraction/src/main/java/org/apache/commons/numbers/fraction/Fraction.java
@@ -706,7 +706,17 @@
 
     @Override
     public int hashCode() {
-        return 37 * (37 * 17 + numerator) + denominator;
+        // Incorporate the sign and absolute values of the numerator and denominator.
+        // Equivalent to
+        // Arrays.hashCode(new int[] {signum(), Math.abs(numerator), Math.abs(denominator)})
+        // int hash = 1;
+        // hash = 31 * hash + signum();
+        // hash = 31 * hash + Math.abs(numerator);
+        // hash = 31 * hash + Math.abs(denominator);
+        // Note: x * Integer.signum(x) is equivalent to Math.abs(x).
+        final int numS = Integer.signum(numerator);
+        final int denS = Integer.signum(denominator);
+        return 31 * (31 * (31 + numS * denS) + numerator * numS) + denominator * denS;
     }
 
     /**
diff --git a/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/BigFractionTest.java b/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/BigFractionTest.java
index e3a611b..4d3377c 100644
--- a/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/BigFractionTest.java
+++ b/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/BigFractionTest.java
@@ -19,13 +19,12 @@
 import java.math.BigDecimal;
 import java.math.BigInteger;
 import java.math.RoundingMode;
+import java.util.Arrays;
 import org.apache.commons.numbers.core.TestUtils;
 
 import org.junit.jupiter.api.Assertions;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
-
 public class BigFractionTest {
 
     private static void assertFraction(long expectedNumerator, long expectedDenominator, BigFraction actual) {
@@ -595,7 +594,6 @@
         Assertions.assertEquals(new BigDecimal("0.333"), BigFraction.of(1, 3).bigDecimalValue(3, RoundingMode.DOWN));
     }
 
-    @Disabled
     @Test
     public void testEqualsAndHashCode() {
         BigFraction zero = BigFraction.of(0, 1);
@@ -649,6 +647,12 @@
         Assertions.assertNotSame(f1, f2, "Do not call this assertion with the same object");
         Assertions.assertEquals(f1, f2);
         Assertions.assertEquals(f1.hashCode(), f2.hashCode(), "Equal fractions have different hashCode");
+        // Check the hashcode computation.
+        // This is not mandated but is a recommendation.
+        final int expected = Arrays.hashCode(new Object[] {f1.signum(),
+                                                           f1.getNumerator().abs(),
+                                                           f1.getDenominator().abs()});
+        Assertions.assertEquals(expected, f1.hashCode(), "Hashcode not equal to using Arrays.hashCode");
     }
 
     @Test
diff --git a/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/FractionTest.java b/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/FractionTest.java
index 0888a75..ada4269 100644
--- a/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/FractionTest.java
+++ b/commons-numbers-fraction/src/test/java/org/apache/commons/numbers/fraction/FractionTest.java
@@ -16,13 +16,12 @@
  */
 package org.apache.commons.numbers.fraction;
 
+import java.util.Arrays;
 import org.apache.commons.numbers.core.TestUtils;
 
 import org.junit.jupiter.api.Assertions;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
-
 /**
  */
 public class FractionTest {
@@ -427,7 +426,6 @@
         );
     }
 
-    @Disabled
     @Test
     public void testEqualsAndHashCode() {
         Fraction zero = Fraction.of(0, 1);
@@ -492,6 +490,12 @@
         Assertions.assertNotSame(f1, f2, "Do not call this assertion with the same object");
         Assertions.assertEquals(f1, f2);
         Assertions.assertEquals(f1.hashCode(), f2.hashCode(), "Equal fractions have different hashCode");
+        // Check the hashcode computation.
+        // This is not mandated but is a recommendation.
+        final int expected = Arrays.hashCode(new int[] {f1.signum(),
+                                                        Math.abs(f1.getNumerator()),
+                                                        Math.abs(f1.getDenominator())});
+        Assertions.assertEquals(expected, f1.hashCode(), "Hashcode not equal to using Arrays.hashCode");
     }
 
     @Test