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
Answer:
S
Step-by-step explanation:
Answer:
The table provides information on road accidents reported to the police for the days in December.
Accidents reportedFrequency1 - 7178 - 12713 - 17518 - 222
Estimate the mean.
Give your answer rounded to 1 DP
Answer:
1,200+300=1,500
Step-by-step explanation:
Answer:
Step-by-step explanation:
P = 4x(x - 3) + 4y(y - 3) + 8xy
= 4x² - 12x + 4y² - 12y + 8xy
= (4x² + 8xy + 4y²) - (12x + 12y)
= 4(x² + 2xy + y²) - 12(x + y)
= 4(x + y)² - 12(x + y)
x+y =2 ⇒ P = 4.2² - 12.2 = 16 - 24 = -8
