Answer:
The ratio of boys to girls to 5:7
Let the number of boys be 5x
Let the number of girls be 7x
5x = 30
x = 6
Now just plug in 6 for the x in 7x
and number of girls 7 x 6 = 42
To find the area, use A= bh (base x height), or A = lw (length x width)
There are 3 feet in 1 yard
3 x 5 = 15
4 x 3 = 12
15 x 12 = 180
The flower bed is 180 ft²
hope this helps
Answer:
Step-by-step explanation:
Let Freda's sum = x
Donnie has 3/4 x
He spends 63 dollars. His sum is now
3/4x - 63
Now the equation looks like this
6(3/4x - 63) = x Remove the brackets
6*3/4 x - 378 =x
6 * 3/4 = 4 1/2
4 1/2 x - 378 = x Add 378 to both sides
4 1/2 x = x + 378 Subtract x from both sides
3.5 x = 378 Divide by 3.5
x = 378 /3.5
x = 108
Since x = 108, that's how much Freda had. (She spent nothing).
Answer:
Step-by-step explanation:
This is a Combination (as in permutation vs combination) question the symbol (n r) refers to "n choose r". This is sometimes written as nCr
i.e the question is asking you to find how many combinations each will yield when you chose r items from n item without repetition and order does not matter.
I will only do the first question for you and you can just follow the same steps to solve the rest of the questions.
Recall that

Consider question a) we are given (5 1) or ₅C₁
we can see that n = 5 and r = 1
If we substitute this into the formula:
₅C₁ = (5!) / [ (1!)(5- 1)!]
= (5!) / [ (5- 1)!]
= (5!) / (4!)
= (5·4·3·2·1) / (4·3·2·1)
= 5
hence ₅C₁ = 5