JavaScript Quiz #001

Welcome to the very first day of #100DaysOfQuiz! Each day I’ll drop one bite-sized JavaScript teaser, followed by a crystal-clear explanation and a live code runner so you can test yourself instantly.

Question

What will the following code print?

console.log(2 + '2' - 1);

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Short Answer

✅Final output: 21

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Deep Dive

1. Step 1: 2 + '2'
   The + operator is special in JavaScript. If **either** operand is a string, it performs **string concatenation**. So the number 2 is coerced into the string "2" and glued to "2", giving "22".
2. Step 2: "22" - 1
   The - operator has no string overload; it **always** subtracts numbers. JavaScript coerces "22" → 22, then subtracts 1, yielding 21.

Key takeaway: + is the concatenation trap; every other arithmetic operator (- * / %) forces both sides to numbers.

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Try It Yourself – No External Tabs

Edit the code below and hit Run. The console output appears instantly.

(The runner is a tiny sandbox hosted by me; zero tracking, zero ads.)

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