Answer:
Step-by-step explanation:
Let the numbers be x and y
<h3>Given condition:</h3>
x + y = 48 --------(1)
y = 7x -------------(2)
Put Eq. (2) in (1)
x + 7x = 48
8x = 48
Divide 8 to both sides
x = 48/8
<h3>x = 6</h3>
Put x = 6 in Eq. (2)
y = 7 (6)
<h3>y = 42</h3>
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The total number of articles is 14 and only 7 can be published. Since what is asked is the ways to assemble the 7 articles, this is a permutation problem.
14P7 = <span>17297280 ways
If order is not of concern, the problem is just a combination problem
14C7 = </span><span>3432 ways</span><span />
The student made the mistake in Step 2.
It should be m∠o + m∠p = 180 (Supplementary angles)
If this is corrected, then, since m∠m + m∠n + m∠o = 180 from Step 1,
we have,
m∠m + m∠n + m∠o = m∠o + m∠p which is Step 3.
Cancelling m∠o both sides, we get,
m∠m + m∠n = m∠p which is Step 4.
