Ni : Zn: Cu = 7:2:9 =7x : 2x : 9x
7x+2x+9x = 3.8
18x=3.8
x=3.8/18=1.9/9≈0.21
Ni: 7x=7*0.21=1.47 ≈1.5 kg
Zn: 2x=2*0.21=0.42≈0.4 kg
Cu: 9x=9*0.21=1.89 ≈1.9 kg
Check 1.5+0.4+1.9 =3.8 True
Total 175 students.
102 students go to movies at least twice a week and 73 students either go 1 times or not going to the movies.
So
Students go 0-1 times per week = 73/175 = 0.4172 = 41.71%
Answer: last option
41.71%
Angles 1 and 3 are supplementary
Answer:
y=-1/4x+2
Step-by-step explanation:
Answer:
y = - 9, y = 3
Step-by-step explanation:
Calculate distance d using the distance formula
d = 
with (x₁, y₁ ) = (2, - 3) and (x₂, y₂ ) = (10, y)
d = 
= 
Given distance between points is 10, then
= 10 ( square both sides )
64 + (y + 3)² = 100 ( subtract 64 from both sides )
(y + 3)² = 36 ( take the square root of both sides )
y + 3 = ±
= ± 6 ( subtract 3 from both sides )
y = - 3 ± 6 , thus
y = - 3 - 6 = - 9
y = - 3 + 6 = 3