# Daily Challenge: Can You Solve It in 20 Seconds?

> A quick mental math challenge tests your ability to follow order of operations without rushing.
- Title: Daily Challenge: Can You Solve It in 20 Seconds? | Shortify
- Summary: A quick mental math challenge tests your ability to follow order of operations without rushing. Solving 84×2-(56÷7+9) in 20 seconds requires careful…
- Keywords: mental math, order of operations, parentheses, calculation challenge, 20 seconds, math test, Daily, Challenge, Solve, Seconds, Psychologies
- Source: Psychologies — https://psychologies.com/culture/savoirs/Le-defi-du-jour-partie-de-ceux-qui-trouveront-la-bonne-reponse-du-premier-coup-2-640552
- Author: La Rédaction
- Published: 2026-09-27T03:05:00+00:00
- Read time: 1 min
- Topics: mental math, order of operations, parentheses, calculation challenge, 20 seconds, math test
## Daily Challenge: Solve in 20 Seconds?
The challenge asks you to solve a mental math problem in 20 seconds without a calculator.

> 84 × 2 - (56 ÷ 7 + 9)
## Why This Challenge Is Tricky
The problem uses familiar numbers and operations but requires careful attention to parentheses and order.

> Parentheses change the calculation rhythm completely.
## Common Mistakes in This Challenge
People often skip parentheses or rush through operations, leading to incorrect answers.

> The brain loves shortcuts but can be tricked by parentheses.
## How to Solve Correctly
First solve inside parentheses: 56 ÷ 7 = 8, then 8 + 9 = 17. Next multiply 84 × 2 = 168. Finally subtract 17 from 168.

> 84 × 2 - (56 ÷ 7 + 9) = 151
## The Real Test
This challenge measures your ability to slow down and follow operations, not advanced math skills.

> The answer is 151, but the real test is attention to detail.
## Key takeaway

Solving 84×2-(56÷7+9) in 20 seconds requires careful attention to parentheses and operations, not advanced math skills.