#DailyBloggingChallenge (135/200)
Some times one questions how the price of an item was decided on. Like take for example pickles, there are multiple options at the store although they all have basically the same ingredients.
One could claim one is paying extra for the brand. That would be fine if the brand was actually good, though lots of times, I have found the no name brand or store brand is better than some specific big name brand.
#DailyBloggingChallenge (139/200)
Let `p` be price of cup and `w` be hourly work cost. Then the cost `C` of preparation per cup is
```
C = p + w * t
```
for time `t` in hours.
If we take a look at the three cup example for satiation of a meal `M`.
```
M = 3 * C = 3 * (p + w * 0.083)
```
Let's take a look at various price points `p = {0.8, 1.5, 3.5}` and various hourly wages `w = {20, 50, 100}`. Then this gives us the table `WP`.
| w\p | 0.8 | 1.5 | 3.5 |
| ------ | ------- | ------- | -------- |
| 20 | 7.4 | 9.5 | 15.5 |
| 50 | 14.5 | 17 | 23 |
| 100 | 27.4 | 29.5 | 35.5 |
Now considering that whole food costs a fraction `p_f` of the price of convenience food, though in return needs more prep time `t_f`.
This gives us the new equation of
```
C_f = p_f * p + w * t * t_f
```
and
```
M_f = 3 * C_f = 3 * (p_f * p + w * t * t_f)
```
We will look at `p_f = {0.5, 0.8}` and `t_f = {5, 10}`; only on the last two columns of the previous table `WP`.
First we will multiply `p_f * p` and `t * t_f`, so that we can use the equation `M`.
Let table `P` be
| `p_f\p` | 1.5 | 3.5 |
| ---------------- | ------- | ------- |
| 0.5 | 0.75 | 1.75 |
| 0.8 | 1.2 | 2.8 |
and table `T` be
| `t_f\t` | 0.083 |
| ---------------- | --------- |
| 5 | 0.42 |
| 10 | 0.83 |
This give us the equation
```
M_f = 3 * C_f = 3 * (P + w * T)
```
and the table `WTF`
| `w\t_f` | 0.42 | 0.83 |
| ---------------- | -------- | ------- |
| 20 | 8.4 | 16.6 |
| 50 | 21 | 41.5 |
| 100 | 42 | 83 |
with this we can finally calculate the table `WPF`
| `w*t_f\p_f` | 0.75 | 1.2 | 1.75 | 2.8 |
| ------ | ------- | ------- | -------- |
| 8.4 | 27.45 | 28.8 | 30.45 | 33.6 |
| 16.6 | 52.5 | 53.85 | 55.5 | 58.65 |
| 21 | 65.25 | 66.6 | 68.25 | 71.4 |
| 42 | 130.5 | 131.85 | 133.5 | 136.65 |
| 83 | 251.25 | 252.6 | 254.25 | 257.4 |
since 41.5 and 42 are close, we omitted the prior one.
The table `WPF` shows that considering one's own wage price for food prep, then a meal becomes quite expensive.
So next time one complains how expensive a meal is at the #restaurant, one can compare how expensive it would be if one prepped it oneself.