diff --git a/libraries/src/test/java/com/baeldung/hll/HLLUnitTest.java b/libraries/src/test/java/com/baeldung/hll/HLLUnitTest.java
index 2745e1e681..8d09c99f0f 100644
--- a/libraries/src/test/java/com/baeldung/hll/HLLUnitTest.java
+++ b/libraries/src/test/java/com/baeldung/hll/HLLUnitTest.java
@@ -4,6 +4,7 @@ package com.baeldung.hll;
 import com.google.common.hash.HashFunction;
 import com.google.common.hash.Hashing;
 import net.agkn.hll.HLL;
+import org.assertj.core.data.Offset;
 import org.junit.Test;
 
 import java.util.stream.LongStream;
@@ -15,8 +16,8 @@ public class HLLUnitTest {
     @Test
     public void givenHLL_whenAddHugeAmountOfNumbers_thenShouldReturnEstimatedCardinality() {
         //given
-        int numberOfElements = 100_000_000;
-        int toleratedDifference = 1_000_000;
+        long numberOfElements = 100_000_000;
+        long toleratedDifference = 1_000_000;
         HashFunction hashFunction = Hashing.murmur3_128();
         HLL hll = new HLL(14, 5);
 
@@ -29,14 +30,14 @@ public class HLLUnitTest {
 
         //then
         long cardinality = hll.cardinality();
-        assertThat(isSimilarTo(cardinality, numberOfElements, toleratedDifference)).isTrue();
+        assertThat(cardinality).isCloseTo(numberOfElements, Offset.offset(toleratedDifference));
     }
 
     @Test
     public void givenTwoHLLs_whenAddHugeAmountOfNumbers_thenShouldReturnEstimatedCardinalityForUnionOfHLLs() {
         //given
-        int numberOfElements = 100_000_000;
-        int toleratedDifference = 1_000_000;
+        long numberOfElements = 100_000_000;
+        long toleratedDifference = 1_000_000;
         HashFunction hashFunction = Hashing.murmur3_128();
         HLL firstHll = new HLL(15, 5);
         HLL secondHLL = new HLL(15, 5);
@@ -57,12 +58,6 @@ public class HLLUnitTest {
         //then
         firstHll.union(secondHLL);
         long cardinality = firstHll.cardinality();
-        assertThat(isSimilarTo(cardinality, numberOfElements * 2,
-                toleratedDifference * 2)).isTrue();
-    }
-
-    private boolean isSimilarTo(long cardinality, int numberOfElements, int maxToleratedDifference) {
-        System.out.println(cardinality);
-        return Math.abs(cardinality - numberOfElements) <= maxToleratedDifference;
+        assertThat(cardinality).isCloseTo(numberOfElements * 2, Offset.offset(toleratedDifference * 2));
     }
 }