Welcome to the
Speed Multiply Trick
For Two Digit Numbers

Somewhere hidden behind this page and locked with a secret password is a treasure page bursting with FREE treasure.

To find it, all you need to do is learn how to SPEED MULTIPLY. Then solve the password clue problems.

When you KNOW the password

THE SPEED MULTIPLY TRICK:
Works best with two digit numbers.
*The following text is taken as an example from the book
cover. We at themathlab.com highly recommend this book if you really want to become a mental math whiz.


"To multiply two 2-digit numbers without showing work, first multiply the ones digits together, then 'cross-multiply,' and finally multiply the tens digits together.

Make sure to carry whenever a product exceeds 9. As you will see in the examples below, you must work your way from right to left to perform this trick.

EX 1:
12 x 23 = ?

  1. Multiply the ones digits: 2x3=6 (ones digit answer).
  2. Cross-multiply and add: (1x3)+(2x2)=7 (tens-digit answer).
  3. Multiply the tens digits: 1x2=2 (hundreds-digit answer).
  4. Combine: 276 (the answer).

Thought Process Summary

this will save you lots of time


EX 2:
31 x 24 = ?

  1. Multiply the ones digits: 1x4=4 (ones digits answer).
  2. Cross-multiply and add: (3x4)+(1x2)=14 (use the 4 as the tens-digit answer, and carry the 1).
  3. Multiply the tens digits, and add the 1: (3x2)+1=7 (hundreds-digit answer).
  4. Combine: 744 (the answer).

Thought Process Summary

don't forget to carry


*Number-Power Note: This trick will also work on numbers with zeroes and decimal points.

Also as you are cross-multiplying, it is generally easier to begin with the larger product and then add the smaller product."


Password Clues

Use the SPEED MULTIPLY TRICK to do the following problems in order. When you find each answer, look in the left column to find its corresponding letter and write this letter.

  1. x13
    x21
    -----
  2. x22
    x14
    -----
  3. x32
    x15
    -----
  4. x42
    x42
    -----
  5. x51
    x33
    -----
  6. x25
    x13
    -----
  7. x44
    x11
    -----
  8. x53
    x34
    -----
  9. x14
    x52
    -----
  10. 43
    x45
    -----
  11. .35
    x 41
    ------
  12. .23
    x 55
    -----
  13. .54
    x 15
    -----
  14. .21
    x 51
    -----
  15. .34
    x 34
    -----
  16. .12
    x 45
    -----
  17. Now cross of every o,b,r,and t. You will be left with the password.

480 = u

1,802 = k

273 = o

1,071 = o

325 = r

810 = l

728 = a

308 = f

540 = c

484 = t

1,764 = b

1,435 = b

1,156 = i

1,265 = e

1,935 = d

1,683 = n

When you KNOW the password

To learn even more of these mental math tricks try the book
cover

CD cover "Do a little dance, make a little love, get DOWN tonight." Listen to samples of the A Night at the Roxbury CD.

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