Kim has 120 cards in a box. She gave 6/10 of cards to Maddy. How many cards did Kim have left in the box?
1 answer:
In order to find out the answer to this question,, you must multiply 120 by 
120 x
Now that we have the expression,, we can start to solve. The first step to solve this problem is to reduce the numbers with 10
12 x 6
Then we multiply the numbers together to see how many cards Kim gave to Maddy.
72
Finally,, we need to subtract 72 from 120 to find out how many cards are left in the box.
120 - 72 = 45
This means that Kim has 45 cards left in the box.
Let me know if you have any further questions
:)
120 x
Now that we have the expression,, we can start to solve. The first step to solve this problem is to reduce the numbers with 10
12 x 6
Then we multiply the numbers together to see how many cards Kim gave to Maddy.
72
Finally,, we need to subtract 72 from 120 to find out how many cards are left in the box.
120 - 72 = 45
This means that Kim has 45 cards left in the box.
Let me know if you have any further questions
:)
You might be interested in
Applying the formula, you have:
A = the number is prime
B = the number is odd
I assume that with "random" you imply that all numbers can be chosen with the same probability. So, we have
because 4 out of 8 numbers are prime: 2, 3, 5 and 7.
Similarly, we have
because 4 out of 8 numbers are odd: 1, 3, 5 and 7.
Finally,
because 3 out of 8 numbers are prime and odd: 3, 5 and 7.
So, applying the formula, we have
Note:
I think that it is important to have a clear understanding of what's happening from a conceptual point of you: conditional probability simply changes the space you're working with: you are not asking "what is the probability that a random number, taken from 1 to 8, is prime?"
Rather, you are adding a bit of information, because you are asking "what is the probability that a random number, taken from 1 to 8, is prime, knowing that it's odd?"
So, we're not working anymore with the space {1,2,3,4,5,6,7,8}, but rather with {1,3,5,7} (we already know that our number is odd).
Out of these 4 odd numbers, 3 are primes. This is why the probability of picking a prime number among the odd numbers in {1,2,3,4,5,6,7,8} is 3/4: they are literally 3 out of 4.