the answer would be B ( 4,-5) because when I put them on a graph it came up with the right one
If they went on a 9 mile hike and stopped every 3 miles, they would stop 3 times during the hike.
Answer:
450 ounces
Step-by-step explanation:
We know that the cost of the mixture
must be the cost of the everyday moisturizing lotion
plus the cost of the self-tanning lotion
, which means
.
The cost of any substance will be the cost per ounce of the substance (c), multiplied by the number of ounces (n), which means C=nc, so we have from the previous formula that we have:
![n_m c_m=n_e c_e + n_s c_s](https://tex.z-dn.net/?f=n_m%20c_m%3Dn_e%20c_e%20%2B%20n_s%20c_s)
But we also know that the number of ounces of the mixture must be the sum of the number of ounces of the everyday moisturizing lotion with the number of ounces of the self-tanning lotion, so we have
![n_e c_e + n_s c_s=n_m c_m=(n_e+n_s) c_m=n_e c_m+n_s c_m](https://tex.z-dn.net/?f=n_e%20c_e%20%2B%20n_s%20c_s%3Dn_m%20c_m%3D%28n_e%2Bn_s%29%20c_m%3Dn_e%20c_m%2Bn_s%20c_m)
We want to calculate the number of ounces of the self-tanning lotion (
), so we solve for that variable:
![n_e c_e + n_s c_s=n_e c_m+n_s c_m](https://tex.z-dn.net/?f=n_e%20c_e%20%2B%20n_s%20c_s%3Dn_e%20c_m%2Bn_s%20c_m)
![n_s c_s-n_s c_m=n_e c_m-n_e c_e](https://tex.z-dn.net/?f=n_s%20c_s-n_s%20c_m%3Dn_e%20c_m-n_e%20c_e)
![n_s (c_s-c_m)=n_e(c_m-c_e)](https://tex.z-dn.net/?f=n_s%20%28c_s-c_m%29%3Dn_e%28c_m-c_e%29)
![n_s=\frac{n_e (c_m-c_e)}{(c_s-c_m)}](https://tex.z-dn.net/?f=n_s%3D%5Cfrac%7Bn_e%20%28c_m-c_e%29%7D%7B%28c_s-c_m%29%7D%20)
And substitute our values in this formula, to get:
![n_s=\frac{(700\ ounces) (\$1.6-\$0.7)}{(\$3-\$1.6)}=450\ ounces](https://tex.z-dn.net/?f=n_s%3D%5Cfrac%7B%28700%5C%20ounces%29%20%28%5C%241.6-%5C%240.7%29%7D%7B%28%5C%243-%5C%241.6%29%7D%3D450%5C%20ounces%20)
40 centimeters is the right answer