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2nd grade
Course: 2nd grade > Unit 6
Lesson 4: Length word problemsLength word problems
Sal solves length word problems with addition and subtraction.
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- Here Is The First Question: Sydney Has 10 Friends, Sydney Has 340 pokemon, And She Wants To Find A Way To Give The Same Amount To Her Friends. What Does Sydney Need To Do? Explain.(24 votes)
- Divide 340 mons by 10 friends. You get 34 mons per friend.
340 / 10 = 34
To prove: multiply 10 friends by 34 mons that each friend now owns.
34 * 10 = 340
You get the same amount (340) of mons that Sydney had before splitting them up for her friends.(4 votes)
- Here Is The Next Question: Chloe is going on a field trip with her class and 2 other classes, Each class has the same amount of kids, They all have 26 kids in their class with Chloe, But there is a problem. The bus can ONLY take 56 kids and there are 76 kids, and of course 4 adults are coming and taking a car. The cars can ONLY has 4 people in there. Can everyone fit and who is left out? Explain.(8 votes)
- 2 classes and 4 lucky students from the other class, and no, not everyone will fit.(13 votes)
- how is the answer 12 if it's 5+6=(8 votes)
- 5 + 6 is 11 not 12(3 votes)
- Here is another one: Zoey had 89 marbles then she gave 10 to 2 friends. How many marbles does Zoey have now?(3 votes)
- Maybe 79 because she gave 10 to two friends. Could be 8 and 2 or five and five(4 votes)
- What is the basic formula for this problem I know how to add and subtract and the answer to the questions but how do I set up the problem It confuses me(1 vote)
- Your starting number for the first line in 72cm. If the second line in 14 cm
longer
than 72cm, then you know to add because 14cm is how much longer it is, as apposed to shorter.(4 votes)
- i put the right answers but it says its incorrect(5 votes)
- These videos are so good for a lot of kids to learn about math and english .(5 votes)
- How do you know if your adding or subtracting??(3 votes)
- bye the - sign and the + the + means add and the - means subtract.(5 votes)
- how long is the pink line?!(4 votes)
- It is 86cm long(2 votes)
- I made a word problem here is the problem: jack had 10 Pokémon cards but jack want more he went to the store but it cost 1.00$ jack need to save up how much does jack need to save up explain by using a division(4 votes)
Video transcript
- Dominique drew a 72 centimeter
line on the playground with blue chalk. So the line that she drew, maybe it looks something like that. And that is 72 centimeters, 72 centimeters long. So from there to there is 72 centimeters. And another line with pink chalk that is, so let's do this with pink chalk, another line with pink
chalk that is 14 centimeters longer than the blue line. So let me draw the other line. So the other line, whoops. The other line is going to
be 14 centimeters longer. So maybe it looks something like that. So it's definitely going to be longer. And it's 14 centimeters longer, so if we go from here to here,
that's going to be the same, should maybe make it the same length, this is going to be the 72 centimeters. That's 72 centimeters. But it's also another 14 centimeters. So it's gonna be 14 centimeters longer. So how long is a pink chalk
line that Dominique drew? Well you would just add the 72 plus 14. So 72 plus 14 is equal to, two ones plus four ones is six ones, seven 10s plus one 10 is eight 10s. So this longer line
here is going to be 86, 86 centimeters. Let's do another one. So we're told a cable on
the Golden Gate Bridge is 33 meters long. Another cable is 13 meters
longer than the first cable. Let me do this in a different color. Is 13 meters longer than the first cable. How long would the cables
be if lined up end to end? So they're not just saying,
"How long is the longer one?" Like they did in the last example. They want to know how long are the cables if you line them up end to end? So this first cable is 33 meters. Let me draw it this way. So the first cable is 33 meters long. 33, and actually why
don't I draw it this way, because this is what the cables
would actually look like. So this cable is 33... 33 meters long. Another cable is 13 meters
longer than the first cable. So this other cable right over here is 13 meters longer. So this cable right here
is 13 meters longer. So what's the length of this cable? Well it's going to be the
length of the first one, 33, plus 13. It's 13 meters longer. Plus 13, that gets us... three plus three is six, three plus one is four. This one over here is gonna be 46 meters. Now they didn't just ask, "How
long is the second cable," which is 46 meters. They're asking, "How
long would the cables be "if we lined them up end to end?" So if we lined the 33 meter one, so if we lined up the 33 meter one, and then right next to that, we, right next to that,
put the 46 meter one. So if we did something like that. Well we know that this one
over here is 33 meters, and the next one is 46 meters, so we would have to add
33 plus 46 to figure out how long they would be end to end. And what is that gonna be? So if we say 33 plus 46, plus 46, three ones plus six ones is nine ones, three 10s plus four 10s is 70, sorry... three 10s plus four 10s is seven 10s. So it's going to be 79
meters if we line them up end to end. Let's do one more. Reynaldo has a 36 centimeter scarf. So he has a 36 centimeter scarf. He decides to cut out part of the scarf so it is now only 19 centimeters. How many centimeters did
Reynaldo cut off of his scarf? So let's draw his scarf. So it was a 36 centimeter scarf, so it might've looked something like this. So this was his scarf before,
if I stretch it all out, and it is 36 centimeters, 36 centimeters long. But he cuts part of his scarf so it's only 19 centimeters long. So now it is only 19 centimeters. So after he cut it, it's gonna
look something like this. Actually maybe I'll... actually, I'll draw it in green again. So after he cuts it, his scarf is gonna look
something like this. It's gonna look something like this, where now it's only 19 centimeters. 19 centimeters. So how much did he cut off? Well what he cut off is
going to be the difference between 36 and 19. He would have had to cut off, he would have had to cut off all of this right over here
in order to get it down to 19. So much would he have to cut off? Well this right over here
is going to be 36 minus 19. It's the difference between 36 and 19. So let's figure out what that is. It's going to be 36 minus 19. So let's see, if we... we have six ones, we want
to take away nine ones. So let's do a little bit of regrouping. Let's take one of our 10s here, so instead of three 10s, we have two 10s. And then if we add that
10 to the ones place, instead of six ones,
we're gonna have 16 ones. 16 minus nine is seven. Two 10s minus one 10 is one 10. So he would have had to cut off 17 centimeters of his scarf. If he started with 36 centimeters, he cuts off 17 centimeters, he's going to be left with 19 centimeters. And you could do that
the other way around. You could start with 36, you could cut 17, and see what you end up with. You're going to see
that you end up with 19.