Easy process and easy questions, simple map filter and reduce questions, Javascript interview for frontend developer. const arr = [{ name: 'John', age: 25, city: 'New York' }, { name: 'Jane', age: 30, city: 'Chicago' }, { name: 'Bob', age: 20, city: 'San Francisco' }, { name: 'Mary', age: 27, city: 'New York' }, ] const obj = { city: 'New York', age: 25 } // Expected outcome: [ {name: 'John', age: 25, city: 'New York'}, {name: 'Mary', age: 27, city: 'New York'}, ]; const result = arr.filter(el => { for(let key of Object.keys(obj)) { if (obj[key] === el[key]) { return true; } } }) result