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1.4 Multiplication

MULTIPLICATION: A SHORTCUT TO REPEATED ADDITION

Multiplication is a simpler way of doing repeated addition. Suppose Ron can do 30 push-ups in one minute. If he maintained a steady pace, how many push-ups could he do in five minutes? You could add 30 + 30 + 30 + 30 + 30, or you could multiply 30 × 5 to arrive at the answer of 150 push-ups. Some words and symbols used in multiplication are times, the product of, the "×" sign, or a dot like "•". Sometimes numbers that are being multiplied will be put in parentheses (30)(5)=150. 

Example 1 - Each person on your six-person crew is carrying five quarts of water. How many quarts of water does your crew have in total? 

multiplication graphic


The multiplication problem would be 5 × 6 = 30.
This process is the same as adding 5 six times.

When larger numbers are involved, multiplication is much easier than the repeated addition.

Example 2 - Multiply 17 by 63.

multiplication example 

Step 1. Multiply the top number by the number in the ones spot, which is 3.
17 × 3 = 51

Step 2. Multiply by the number in the tens spot, or 60, by putting a "0" in the ones place and multiplying 17 × 6.
17 × 60 = 1020

Step 3. Add these together.
17 × 63 = 51 + 1020 = 1071

Example 3 - Multiply 374 × 261.

Follow the same steps as shown above.

Step 1. Multiply 374 by 1.

Step 2. Multiply by 60. Put a "0" in the ones place and then multiply 374 by 6.

Step 3. Multiply by 200. Put "0" in the ones and tens places and then multiply 374 by 2.

Step 4. Add the numbers. 
374 + 22,440 + 74,800 = 97,614


The answer to 374 × 261 is 97,614. 
 

MULTIPLYING SIGNED NUMBERS

When multiplying two numbers with the same sign, the answer will be a positive number. A positive number times a positive number always gives a positive answer.
5 × 5 = 25
4 × 8 = 32
2 × 6 = 12

A negative number times a negative number always gives a positive answer.
-5 × (-5) = 25
-5 × (-10) = 50
-9 × (-7) = 63

A positive number times a negative number always gives a negative answer.
5 × (-5) = -25
-70 × 8 = -560
24 × (-2) = -48

 

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NWCG Equipment Technology Committee Releases Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention

Date: November 14, 2024
Contact: Equipment Technology Committee

The Equipment Technology Committee (ETC) has released Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention. Misaligned toolless fuel caps on Stihl chainsaws have led to recurring fuel spillage, fuel ignition, and burn injuries during wildland fire management operations.

This Safety Warning is intended to highlight the details and recommended procedures for the installation of a Stihl chainsaw toolless fuel cap, as well as how to identify and correct a misaligned, damaged, or broken fuel cap to help prevent fuel spillage.

References:

NWCG Safety Warning: 24-001 Stihl Chainsaw Toolless Fuel Cap Spill Prevention

Advertencia de equipos 24-001: Prevención de derrames de la tapa de combustible sin herramientas de la motosierra Stihl

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The Incident Position Standards and Next Generation Position Task Book are now available for Equipment Time Recorder (EQTR)

Date: November 13, 2024
Contact: Incident Business Committee

NWCG is excited to announce that the NWCG Incident Position Standards for Equipment Time Recorder, PMS 350-51 and NWCG Position Task Book for Equipment Time Recorder (EQTR), PMS 311-51 are now available.

The Performance Support Package, which for EQTR, includes the Incident Position Standards and Next Generation Position Task Book were developed through the Incident Performance and Training Modernization (IPTM) effort. The Performance Support Package will support trainees, those qualified in the position, and evaluators.

References:

NWCG Equipment Time Recorder Position Page

NWCG Incident Position Standards for Equipment Time Recorder, PMS 350-51

NWCG Position Task Book for Equipment Time Recorder (EQTR), PMS 311-51

The Incident Position Standards and Next Generation Position Task Book are now available for Personnel Time Recorder (PTRC)

Date: November 13, 2024
Contact: Incident Business Committee

NWCG is excited to announce that the NWCG Incident Position Standards for Personnel Time Recorder, PMS 350-53 and NWCG Position Task Book for Personnel Time Recorder (PTRC), PMS 311-53 are now available.

The Performance Support Package, which for PTRC, includes the Incident Position Standards and Next Generation Position Task Book were developed through the Incident Performance and Training Modernization (IPTM) effort. The Performance Support Package will support trainees, those qualified in the position, and evaluators.

References:

NWCG Personnel Time Recorder Position Page

NWCG Incident Position Standards for Personnel Time Recorder, PMS 350-53

NWCG Position Task Book for Personnel Time Recorder (PTRC), PMS 311-53

NWCG Risk Management Committee Releases Safety Bulletin: 24-001 Use of Respirators on Wildland Fires

Date: November 7, 2024
Contact: Risk Management Committee

The Risk Management Committee (RMC) has released Safety Bulletin: 24-001 Use of Respirators on Wildland Fires. As wildland fire respirators are available through several established vendors, wildland fire personnel need to understand regulations and limitations of respirator use in the workplace.

Safety Bulletin 24-001 outlines the following topics regarding respirator use for wildland fires:

  • Requirements for Respirator Use
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  • Unknown Risks of Respirator Use

This bulletin also provides mitigation recommendations to help reduce smoke exposure for wildland firefighting efforts.

References:

NWCG Safety Bulletin: 24-001 Use of Respirators on Wildland Fires

NWCG Smoke Management Guide for Prescribed Fire, PMS 420-3

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