220/400 = 55%
100%- 55% = 45%
there were 45% more girls than there were boys.
Answer:
Step-by-step explanation:
S.I= PTR/100
=9000*(15/12)*2/100
=90*5/2
=450/2
=225
Answer:
B. (-0.73, 0), (2.73, 0)
Step-by-step explanation:
vertex form of a parabola
y = a(x-h)^2 +k
y = a(x-1)^2 -9
substitute the point in to find a
-6 = a (0-1) ^2 -9
-6 = a *1 -9
add 9 to each side
-6+9 = a -9+9
3 =a
y = 3(x-1)^2 -9
FOIL
y = 3(x-1)(x-1) -9
y = 3(x^2-2x+1) -9
distribute
y = 3x^2-6x+3-9
combine like terms
y = 3x^2 -6x -6
factor out 3
y= 3(x^2 - 2x -2)
set = 0
0 = 3(x^2 - 2x -2)
x^2 - 2x -2 =0
using the quadratic formula
-b±sqrt(b^2 -4ac)
----------------------
2a
-(-2) ± sqrt(2^2 - 4(1)(-2))
-------------------------------
2(1)
2 ± sqrt(4+8)
------------------
2
2±sqrt(12)
---------------
2
2±2sqrt(3)
----------------
2
1±sqrt(3)
roots: 2.73, and -.73
150 114 84 60 42 30 24
from right to left the difference between numbers is increasing by an extra 6 each time
24 +6 =30 + 12 =42 +18 = 60 etc
Answer:
1.5 inches of steel
Step-by-step explanation:
450/300
=1.5 in.
