Subtraction word problems within 10 | Basic addition and subtraction | Early Math | Khan Academy

Summary

The video explores how to solve a basic subtraction word problem involving sharks at a reef. It starts by setting a scene with 10 sharks, of which 2 swim away. The task is to determine how many sharks remain. By physically counting down from 10 sharks and subtracting 2, viewers learn that 8 sharks are left. This simple exercise is aimed at helping beginners understand basic subtraction concepts through visualization and step-by-step problem-solving.

Highlights

• Two sharks swimming away from a group of ten makes subtraction fun! 🌊
• Counting remaining sharks helps solve the puzzle easily! 🎣
• Using real-life scenarios like sharks makes math relatable and engaging 🦈

Key Takeaways

• Understanding subtraction through visual aids simplifies learning 🦈
• Engaging with word problems helps build mathematical thinking 🧠
• Counting down from a total helps kids grasp subtraction basics 🧮

Overview

In this playful segment on subtraction, Khan Academy brings reef sharks into the mix, making math learning visually engaging and interactive. Viewers are shown a scene with 10 sharks at a reef, setting up the classic subtraction problem when two of these marine creatures swim away.

Exploring this further, the video delves into counting the sharks one by one as it reinforces the notion of 'taking away' in subtraction. By physically removing sharks from the count, learners can easily follow the logic behind subtracting two from ten, leading to an answer of eight remaining sharks.

The use of real-world scenarios, like sharks swimming away, aids young learners in connecting math to the world around them. This method not only strengthens their arithmetic skills but also encourages them to think critically about everyday situations, using math as a tool for understanding.

Chapters

• 00:00 - 00:30: Introduction to the Scenario The chapter introduces a scenario featuring 10 sharks at a reef. The narrator confirms the presence of 10 sharks just as previously stated. Then, two sharks swim away, prompting an inquiry to calculate how many sharks remain at the reef.
• 00:30 - 01:00: Solving the Problem The chapter 'Solving the Problem' focuses on basic subtraction using a visual example. The narrator explains the concept of subtracting two from ten by using an illustrative scenario involving sharks. Initially, there are ten sharks, and after taking away two, eight remain. This helps to emphasize the subtraction equation: 10 - 2 = 8.

Subtraction word problems within 10 | Basic addition and subtraction | Early Math | Khan Academy Transcription

• 00:00 - 00:30 - [Voiceover] There were 10 sharks at the reef. And we see, there's one, two, three, four, five, six, seven, eight, nine, 10 sharks, just like they told us. Two sharks swam away, I was gonna say ran away, (laughs), they swam away. How many sharks are left? So, let's think about it. There were 10 sharks at the reef and two of them, two of them, swam away, so how many sharks are left? How many sharks are left?
• 00:30 - 01:00 Well, what's 10 minus two going to be equal to? Well, we could look up here if we had 10 pictures of sharks and we were to take away, we were to take away one and then two, how many are going to be left? Well, we see we have one, two, three, four, five, six, seven, and eight. So, 10 minus two, 10 taking away two sharks, the two sharks that swam away, is going to be equal to eight.