Roger buys a 35 x 35 foot lot to source rocks for his pet rock project. How many square feet did he buy?

Question

Quizplus · Accepted Answer

35 x 35 is 1225 square feet.
Key Takeaway: To square any number that ends in 5, use this trick.
Take the first digit of the number, in this case 3. Multiply that by itself and the next consecutive digit, which is 4.
So far, we have 3 x (3+1) = 12. Then, simply put 25 on the end, which results in 1225. This trick works for squaring any number that ends in 5.
So far, we have 3 x (3+1) = 12. Then, simply put 25 on the end, which results in 1225. This trick works for squaring any number that ends in 5.

Roger Buys a 35 X 35 Foot Lot to Source