BRAINLIEST IF ALL ARE CORRECT!

A) How many 4-digit numbers are multiples of BOTH 2 and 5?
B) How many 4-digit numbers are multiples of at least one of these two numbers: 2, 5?
C) How many 4-digit numbers are neither multiples of 2 nor multiples of 5?

A) 900

B) 5400

C) 3600

Step-by-step explanation:

A) Number of 4 digit multiples of 5:

(9999-1000+1)/5= 1800

[I added one to the 9999-1000 because it includes 9999]

Now, out of those 1800 numbers that are divisible by 5, 900 of them are even. (so they are divisible by 10 [or 5 and 2])

Therefore, the answer to A is 900

B) Number of 4 digit multiples of 2:

(9999-1000+1)/2= 4500

This means that there are 4500 even 4 digit numbers.

We have already figured out that there are 900 numbers that are divisible by both 5 and 2. 1800-900=900 4-digit numbers that are not divisible by 2, but are divisible by 5.

So if we add the 4500 (numbers that are divisible by 2) and the 900 (numbers that are only divisible by 5, but not 10), we get 5400.

C) There are 9999-1000+1= 9000 4-digit numbers. We know that there are 5400 numbers that are divisible by either 5 or 2, so 9000-5400=3600

Feel free to ask any questions! :)

step-by-step explanation:

the ratio of red paint to blue paint is always 9/7. that means that, whatever x's value, (4x+12)/(4x-4) has that same ratio. so, set up an equation and cross-multiply to solve for x:

9/7 = (4x+12)/(4x-4)

9(4x-4) = 7(4x+12)

36x - 36 = 28x + 84

8x - 36 = 84

8x = 120

x = 15

the weight of the object inside the box!