When you are substituting equations, all you are doing is plugging in variables. Lets do an example..something random but easy...
y = 2x - 3
4x + 2y = 10
So since 2x + 3 equals y we are going to plug in those numbers into the second equation.
4x + 2(2x - 3) = 10
Now we distribute
4x + 4x - 6 = 10
Combine like terms.
8x - 6 = 10
Add 6 to both sides.
8x = 16
Divide.
x = 2
And thats how you substitute equations.
I hope this helps love! :)
Answer:
proportion of orange juice = 4/9
Step-by-step explanation:
Given:
20 mL orange juice
10 mL apple juice
15 mL coconut milk
for a total of (20+10+15)=45 mL of cocktail
Proportion of orange juice in cocktail
= 20/45
= 4/9
The exam scores are distributed normally with mean 72 and standard deviation 5.
Recall the empirical (68 - 95 - 99.7) rule, which says that approximately 95% of a normal distribution lies within two standard deviations of the mean. Put another way,
Also recall that the normal distribution is symmetric about its mean. This means that
From this last equation, it follows that
That is, about 47.5% of the students scored between 72 and 87 on the exam.