If you're seeing this message, it means we're having trouble loading external resources on our website.

Hvis du sidder bag et internet-filter, skal du sikre, at domænerne ***. kastatic.org** og ***.kasandbox.org** ikke er blokeret.

Hovedindhold

Aktuel tid:0:00Samlet varighed:3:09

- Let's do a few examples
of writing expressions to help us solve word problems. So they tell us Susie ran a race. She ran five miles an hour, and the race took her t hours to complete. How long was the race? Write your answer as an expression. Alright, if we're trying to
figure out the number of miles, you'd want to take her speed,
which is in miles per hour, so five miles per hour
times the number of hours. So the number of hours is t, so you can literally just
write that as five t. Five t literally means five times t. Now another way you could have done it is you could have used this
little dot symbol here. This is not a decimal, it
sits higher than a decimal, and it means multiplication,
five times t, either of these, five dot t or five t means
five times t, it makes sense. You take your speed times your time, and you'll figure out how
far you actually went. Let me check my answer here. Let's do a few more of these. The Running Aces card team won $548 playing poker in tournaments last year. The winnings were split
evenly among the p players. How much of money did each, I guess you'd say how much money, not how much of money, it's a grammatical error. How much money did each player receive? Write your answer as an expression. So they had $548, and they
had to split it evenly among the p players, so
they're gonna split it, so I'm just gonna go backslash here, or I literally could have just clicked on this as well, 548 divided by p. I'm gonna divide the
amount of money we got amongst the number of players. So that's how much money each
player actually receives. Let's check the answer,
we've got it right. Let's do a few more of these. Phil received a prize of x
dollars from a poker tournament. The tournament cost him $100 to enter. What were Phil's net
winnings from the tournament? Write your answer as an expression. Alright, his net winnings, okay. He gets x dollars, but
it's not like he just walks away with x, I means,
he does get the x dollars, but he had to pay something
to enter the tournament. He had to pay $100 to
enter the tournament, so for example, if x
was $105, he wins $105, but if he had to spend $100
to enter the tournament, then his net would be 105 minus 100, or five dollars, so this
is giving us the net. We're getting how much he got, but we're subtracting how
much he actually had to spend. Let's do one more of these. Hillary made 48 chocolate chip
cookies and y sugar cookies. How many total cookies did Hillary make? Well, 48 chocolate chip cookies, and then you add that, the number of sugar cookies she made, and there you have it. That's the total number
of cookies she made. If she made two sugar
cookies, y would be two, and she would've made
a total of 50 cookies. If she made 100 sugar
cookies, then this would be 100 plus 48 which would
be 148 total cookies. So hopefully that gives you
a little bit of practice, and I encourage you to do this exercise so you get a lot more practice.