A relation from a set X to a set Y is called a function if each element of X is related to exactly one element in Y. That is, given an element x in X, there is only one element in Y that x isrelated to. For example, consider thefollowing sets X and Y.
From the amounts that are given, the ratio of the earnings will be 3:2:1.
<h3>How to calculate ratio</h3>
From the information, the eldest earns R270, the middle child earns R180 and the youngest earns R90.
Therefore, the common factor to the numbers will be 90. Therefore, the ratio will be:
270/90 = 3
180/90 = 2
90/90 = 1
The ratio is 3:2:1.
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<h2>
Answer:</h2>
<h2>
Step-by-step explanation:</h2>
We will use the Gaussian elimination method to solve this problem. To do so, let's follow the following steps:
Step 1: Let's multiply first equation by −2. Next, add the result to the second equation. So:
Step 2: Let's multiply first equation by −1. Next, add the result to the third equation. Thus:
Step 3: Let's multiply second equation by −35, Next, add the result to the third equation. Therefore:
Step 4: solve for z, then for y, then for x:
By substituting 
into the first equation, we get the 
. So:
Answer:
Surface area: 18,144m
Volume: 139,968m³
Step-by-step explanation:
Surface area:
72x72 = 5184m on bottom, as well as top
5184+5184= 10368
27x72 for side length = 1944
1944 x 4 sides = 7776
7776+10368 = 18,144m surface area
Volume:
72x72x27 = 139,968m³
