Answer:
the second one I think
Step-by-step explanation:
Answer:
4 boys, 3 girls
Step-by-step explanation:
brothers of John ⇒ x
sisters of John ⇒ y
John has as many brothers as sisters:
- x = y
brothers of Emily ⇒ x + 1 (Emily have the same amount of brother as John, plus one (John))
sisters of Emily ⇒ y -1 (Emily have the same amount of sister as John, minus one (herself))
Emily has twice as many brothers as sisters:
- 2 (y-1) = x+ 1
Now we have a system of 2 equations and 2 variables
x=y (I)
2y - 2 = x + 1 (II)
____________
Replace x in equation II
2y - 2 = y + 1
2y - y = 2 + 1
y = 3
____________
Replace y in equation I
x = y = 3
That mean that John have 3 brothers plus himself, there is 4 boys in the family and John have 3 sister, so there is 3 girls in the family
7/5 = 14/10 = 28/20
Numerator = x
Denominator = x-4
Add 3 to both:
x +3 / (x-4+3)
x+3 = 14
(x-4 +3) = 10 = x-1 = 10
x = 11
Check:
11 -4 = 7 ( denominator is 4 less than the numerator.)
add 3 to both:
11+3 = 14
7+3 = 10
14/10 reduces to 7/5
The original fraction would be 11/7
Answer:
644 cm^2
Step-by-step explanation:
20*5*2 = 200
6*5*2 = 60
20*6 = 120
6*8 = 48
12*4*2 = 96
6*4*2 = 48
12*6 = 72
