Practice Finding Squares 51²-59², 151²-159², 251²-259²
Worksheet Description
Practice finding squares of numbers like 51²–59², 151²–159², 251²–259², and beyond. Apply the mental maths trick online with 100 interactive problems!
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The Worksheet
The detailed description of the worksheet
Learn the trick with our blog post
If you're visiting this worksheet for the first time, we recommend starting with the interactive blog post on this trick . There, you'll see a visual, step-by-step explanation of how this pattern works — including flow charts that make the logic crystal clear. Once you understand the concept, come back here to test your speed and accuracy!
This interactive maths worksheet helps students practice the mental math trick to quickly find squares of numbers from the ranges 51 to 59, 151 to 159, 251 to 259, 351 to 359, 451 to 459 and so on up to 1151 to 1159 — all without using pen and paper!
Your task is to apply the trick mentally and enter the answers from left to right, just like how the trick is computed step by step.
This worksheet trains you to recognize the pattern where the number is just above a multiple of 50 — like 51, 151, or 1051 — and use the formula: a² (a 5) b | b² (where a ends in 5 and b is the unit digit).
What about 50², 150², 250², 350², 450², ..., 1150² and so on? Well, if you know the trick for Finding Squares of Numbers Ending in 5, you can calculate them easily.
Left-to-Right Practice
In this worksheet, the entry flow follows the left-to-right mental direction of the trick — you build the larger part (a² (a 5) b) first, then the smaller (b²) part. This makes your practice natural, faster, and consistent with real mental calculation flow.