Question

How I the answer in double digit multiplication

Answer 1

Multiply the problem. Like what is 18x9 it should be like this: 18
x
9
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Multiply 8x9 which is 72, then add a 7 to the next number to bring a ten over. Then multiple 9x1 which = 9, then add the remainder 7, which is 16. 162. (An example)

Answer 2

multiply each digit by each other