Project Euler problems (numbering) : follow naming convention.

Project-Euler/Problem010.js

@@ -0,0 +1,24 @@
+// https://projecteuler.net/problem=10
+
+const isPrime = (number) => {
+  if (number === 2) return true
+  if (number % 2 === 0) return false
+
+  for (let j = 3; j * j <= number; j += 2) {
+    if (number % j === 0) {
+      return false
+    }
+  }
+  return true
+}
+
+const calculateSumOfPrimeNumbers = (maxNumber) => {
+  let sum = 0
+  for (let i = maxNumber - 1; i >= 2; i--) {
+    if (isPrime(parseInt(i)) === true) {
+      sum += i
+    }
+  }
+  return sum
+}
+export { calculateSumOfPrimeNumbers }