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1-js/4-data-structures/8-array-methods/8-average-age/solution.md

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+```js run
+function getAverageAge(users) {
+  return arr.reduce((prev, user) => prev + user.age, 0) / arr.length;
+}
+
+let john = { name: "John", age: 25 }
+let pete = { name: "Pete", age: 30 }
+let mary = { name: "Mary", age: 29 }
+
+let arr = [ john, pete, mary ];
+
+alert( getAverageAge(arr) ); // 28
+```
+

1-js/4-data-structures/8-array-methods/8-average-age/task.md

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+importance: 4
+
+---
+
+# Get average age
+
+Write the function `getAverageAge(users)` that gets an array of objects with property `age` and gets the average.
+
+The formula for the average is `(age1 + age2 + ... + ageN) / N`.
+
+For instance:
+
+```js no-beautify
+let john = { name: "John", age: 25 }
+let pete = { name: "Pete", age: 30 }
+let mary = { name: "Mary", age: 29 }
+
+let arr = [ john, pete, mary ];
+
+alert( getAverageAge(arr) ); // (25+30+29)/3 = 28
+```
+