Travelling in a new country comes with plenty of small challenges, and one of them is quickly converting prices into a familiar currency. When I arrived in South Africa, I found myself regularly estimating ZAR to GBP conversions. The exchange rate hovered around 1 ZAR ≈ £0.04, which meant dividing by 25 to get a rough estimate.
Dividing by 25 isn't difficult, but it's not the most intuitive calculation to do on the fly—especially when paying a bill or making a quick decision. So, I started using a simple Vedic maths trick that makes it much easier.
The Trick: Multiply by 4 and Shift the Decimal
Instead of dividing by 25, which takes a bit of effort, you can multiply by 4 and then move the decimal two places left.
Why It Works
Mathematically, dividing by 25 is the same as multiplying by 4/100. By flipping the operation, we can turn a difficult division into an easy multiplication:
(ZAR × 4)/100 = GBP
Examples in Action
Here's how this method works with real numbers:
ZAR 80
Multiply by 4 → 320
Move decimal → £3.20
ZAR 250
Multiply by 4 → 1000
Move decimal → £10.00
ZAR 375
Multiply by 4 → 1500
Move decimal → £15.00
After a couple of tries, this becomes second nature. It's much quicker than attempting long division in your head or pulling out a calculator every time.
Why This is Useful
When travelling, knowing roughly how much something costs in your home currency helps you make better spending decisions. Whether you're grabbing a coffee, booking a taxi, or tipping at a restaurant, this method gives you a reliable estimate instantly.
If you're heading to South Africa, or anywhere with a 1:25 exchange rate, try this trick. It's a small adjustment, but it makes a big difference.