Multiplication 4 digit by 2 digit numbers. Activity: type the missing numbers, step by step. CCSS.MATH.CONTENT.5.NBT.B.5 Fluently multiply multi-digit whole numbers using the standard algorithm. To use Boom Cards, you must be connected to the Internet. Boom Cards play on modern browsers (Chrome, Safari, Firefox, and Edge). Apps are available for modern Android, iPads, iPhones, and Kindle Fires. For security and privacy, adults must have a Boom Learning account to use and assign Boom Cards. You