javascript object array sum of values in object

JavaScript
arr = [{x:1}, {x:3}]

arr.reduce((accumulator, current) => accumulator + current.x, 0);const fruitTally = fruit.reduce((currentTally, currentFruit) => {
  currentTally[currentFruit] = (currentTally[currentFruit] || 0) + 1 
  return currentTally
} , {})
// returns {"apple":3,"banana":3,"cherry":2,"mango":2,"apricot":1,"guava":2}
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