People in building ---- x (men, women and children)
children --- y
men + women + children = x
(3/7)x + (5/8)(4/7)x + y = x
3x/7 + 5x/14 + y = x
times 14
6x + 5x + 14y = 14x
14y = 3x

y + 220 =x
sub into the other one
14y = 3(y+220)
11y = 660
y = 60
then 14(60) = 3x ---> x = 280

So we have 280 people in the building.

check: 3/7 of 280 are men = 120
leaving 160 women and children
5/8 of these ot 100 are women

so we have 120 men, 100 women and 60 children!

hope this is right! have a great. day

7 0

3 years ago

How many integers are there that consist of four digits (from 1000 to 9999) where the first digit is a 5 or an 8 and the third d

Ostrovityanka [42]

Answer:

1600 integers

Step-by-step explanation:

Since we have a four digit number, there are four digit placements.

For the first digit, since there can either be a 5 or an 8, we have the arrangement as ²P₁ = 2 ways.

For the second digit, we have ten numbers to choose from, so we have ¹⁰P₁ = 10.

For the third digit, since it neither be a 5 or an 8, we have two less digit from the total of ten digits which is 10 - 2 = 8. So, the number of ways of arranging that is ⁸P₁ = 8.

For the last digit, we have ten numbers to choose from, so we have ¹⁰P₁ = 10.

So, the number of integers that can be formed are 2 × 10 × 8 × 10 = 20 × 80 = 1600 integers

5 0

3 years ago

Lynn multiplies 7/8 Times a number the product is less than 7/8 which could be Lynn's number

Brums [2.3K]

Answer: 6/8 <;3..?

Step-by-step explanation:

7 0

2 years ago