Cross Multiplication - Examples, Exercises and Solutions

Vertical Multiplication

Learn the multiplication tables thoroughly and follow these rules:

First rule

Write down the exercise correctly: The ones under the ones, the tens under the tens, and the hundreds under the hundreds.
The number with more digits will be written above the one with fewer digits.

Second rule

When the product is greater than 99 it is stored at the top left and must be remembered to add it to the next result.

Third rule

Before moving on to multiply the next digit, the "numbers stored" at the top left must be erased to avoid confusion.

Fourth rule

We will add a 00 below the result to indicate that we have moved to the next digit, each row of results will start one place to the left in relation to the previous row.

Practice Cross Multiplication

Exercise #1

Darío eats 3 cookies per minute.

How many cookies does Darío eat in an hour?

Video Solution

Step-by-Step Solution

Answer

180 180

Exercise #2

304x

Video Solution

Answer

120 120

Exercise #3

196x

Video Solution

Answer

114 114

Exercise #4

285x

Video Solution

Answer

140 140

Exercise #5

247x

Video Solution

Answer

168 168

Exercise #1

266x

Video Solution

Answer

156 156

Exercise #2

533x

Video Solution

Answer

159 159

Exercise #3

822x

Video Solution

Answer

164 164

Exercise #4

365x

Video Solution

Answer

180 180

Exercise #5

259x

Video Solution

Answer

225 225

Exercise #1

773x

Video Solution

Answer

231 231

Exercise #2

328x

Video Solution

Answer

256 256

Exercise #3

624x

Video Solution

Answer

248 248

Exercise #4

863x

Video Solution

Answer

258 258

Exercise #5

913x

Video Solution

Answer

273 273

Topics learned in later sections

  1. Long Division