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Mental Maths - no working

What is 82019 x 32766? Don't use tools, do the calculation in your head.

6.0s $0.0066 464 tokens

I need to calculate 82019 × 32766.

Let me break this down strategically:

32766 = 32768 - 2 = 2^15 - 2

So: 82019 × 32766 = 82019 × (32768 - 2) = 82019 × 32768 - 82019 × 2 = 82019 × 2^15 - 164038

Now I need to calculate 82019 × 32768: 82019 × 32768 = 82019 × 2^15

Let me multiply by doubling 15 times:

  • 82019 × 2 = 164038
  • 164038 × 2 = 328076
  • 328076 × 2 = 656152
  • 656152 × 2 = 1312304
  • 1312304 × 2 = 2624608
  • 2624608 × 2 = 5249216
  • 5249216 × 2 = 10498432
  • 10498432 × 2 = 20996864
  • 20996864 × 2 = 41993728
  • 41993728 × 2 = 83987456
  • 83987456 × 2 = 167974912
  • 167974912 × 2 = 335949824
  • 335949824 × 2 = 671899648
  • 671899648 × 2 = 1343799296
  • 1343799296 × 2 = 2687598592

Now: 2687598592 - 164038 = 2687434554

82019 × 32766 = 2,687,434,554

Generated 25th Oct 2025