1 / 8

Multiplying Decimals

This resource focuses on effective strategies for multiplying decimals, emphasizing key concepts such as proper number alignment and placeholder usage. It illustrates how to treat decimals as whole numbers during calculations, simplifying the process until the final step, where the decimal point is correctly placed in the final answer. The content includes detailed examples, step-by-step methods for problem-solving, and practice problems to reinforce learning. Ideal for teachers and students looking to enhance their understanding of decimal multiplication.

jubal
Télécharger la présentation

Multiplying Decimals

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Multiplying Decimals Ms. Mayner

  2. or Strategy #1 405 x 59 405 x 59 405 x 9 405 x 50 + 3 6 4 4 5 2 0 2 2 5 0 (5 x 4) = 20 Since there are no other numbers to multiply, write down the 20. (5 x 0) + 2 = 2 Write down the 2. Zero is a place holder. Put a zero in your answer to hold its place. (9 x 0) + 4 = 4 Write down the 4. 5 x 9 = 45 Put the 5 in the answer and carry the 4 (it’s really 40) to the next place value (tens) 5 x 5 = 25 Put the 5 in the answer and carry the 2 (it’s really 20) to the next place value (tens) (9 x 4) = 36 Since there are no other numbers to multiply, write down the 36.

  3. or Strategy #1 405 X 59 405 x 59 405 x 9 405 x 50 + 3 6 4 4 5 2 0 2 2 5 0 23,895 the final answer is

  4. MULTIPLYING DECIMALS: Things you need to know… • Do not line up the decimal points! • Instead, place the number with more digits on top. • Line up the other number underneath, at the right. • Pretend all decimals are whole numbers until the very end • Only look at the decimals when trying to figure out where to put the decimal point in your answer

  5. Example: 5.63 x 3.7 1 Decimal Places 4 2 5.63 two x 3.7 one 1 1 39 4 1 1 + 16 8 9 0 2 0 . 8 3 1 three

  6. Example: 0.53 x 2.618 2.618 has more digits (4) than 0.53 (3), so it goes on top. 3 4 Decimal Places 1 2 2.618 three x 0.53 two 1 7 8 5 4 13 0 9 0 0 + 0 0 0 0 00 . 1 3 8 7 5 4 five

  7. Try This: 6.5 x 15.3 3 1 2 1 15.3 one x 6.5 one 1 7 6 5 + 9 1 8 0 . 9 9 4 5 two

  8. Homework • Multiplying Decimals Page 47 #1 d-g, 2 a-d, 9 • 2.5 Multiplying Decimals Page 48-49 # 3, 5, 9, 11

More Related