こんにちは！「100日後にそろばん完全マスター！」の主です。 Youtube63日目の動画「そろばん4級 5桁×2桁・4桁×3桁・3桁×4桁のやり方」の内容を簡単に解説します。 5桁×2桁のかけ算のやり方 -How to Multiply 5-Digit × 2-Digit Numbers- noteでは、YouTube内の例題2つ目の ...

19 is only 1 away from 20, so you prefer to start by multiplying 20 times 5, which equals 100. Then we need to take away a squadron of 5, because there are actually only 19 squadrons, not 20. 100 take ...

Multiplication of two numbers is easy, right? At primary school we learn how to do long multiplication like this: Methods similar to this go back thousands of years, at least to the ancient Sumerians ...

This summer, battle lines were drawn over a simple math problem: 8 ÷ 2(2 + 2) = ? If you divide 8 by 2 first, you get 16, but if you multiply 2 by (2 + 2) first, you get 1. So, which answer is right?

The process of multiplying three numbers together is similar to the process of multiplying two numbers, but it has one extra step. First, you multiply two of the numbers, then you multiply the third ...