Solve (400+20)×(4+1): Finding Equivalent Expressions

Which equation is the same as the following?

$(400+20)\times(4+1)$

Let's consider that each set of parentheses represent a number.

That is, if we solve the exercises within parentheses we will obtain a multiplication exercise of two numbers.

We solve each of the exercises within parentheses to reveal what the numbers are:

$400+20=420$

$4+1=5$

That is, the exercise we obtained is the multiplication between two numbers:

$420\times5$