Area of trapezoid = (B1 + B2)h/2
B1 = 15 in. + 4 in. + 6 in. = 25 in.
B2 = 15 in.
h = 7 in.
Area = (25 in. + 15 in.)(7 in.)/2 = 140 in.^2
Answer:
a) Matrix B = ![\left[\begin{array}{c}5\\7\\9\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D5%5C%5C7%5C%5C9%5Cend%7Barray%7D%5Cright%5D)
b) Matrix AB = ![\left[\begin{array}{c}2525\\3620\\2845\\3705\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D2525%5C%5C3620%5C%5C2845%5C%5C3705%5Cend%7Barray%7D%5Cright%5D)
c) $12,695
Step-by-step explanation:
Matrix A = ![\left[\begin{array}{ccc}225&110&70\\95&160&225\\280&65&110\\0&240&225\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D225%26110%2670%5C%5C95%26160%26225%5C%5C280%2665%26110%5C%5C0%26240%26225%5Cend%7Barray%7D%5Cright%5D)
a) Matrix B = ![\left[\begin{array}{c}5\\7\\9\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D5%5C%5C7%5C%5C9%5Cend%7Barray%7D%5Cright%5D)
Gross Receipt = AB
.
= ![\left[\begin{array}{c}2525\\3620\\2845\\3705\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bc%7D2525%5C%5C3620%5C%5C2845%5C%5C3705%5Cend%7Barray%7D%5Cright%5D)
c) Total revenue is the sum of receipts from 4 cinemas given in part b
Hence,
Total revenue = $2525 + $3620 + $2845 + $3705 = $12,695
Mark and Don have to sell 11 and 59 marbles respectively.
<em><u>Explanation</u></em>
Lets assume, the number of marbles Mark has is 
As, Don has 4 more than 5 times the number of marbles mark has, so the number of marbles Don has 
Question says that the total number of marbles is 70. So, the equation will be...

<em>So, the number of marbles Mark has = 11 </em>
<em>and the number of marbles Don has =
</em>
11 because 275÷25 is 11. 11 calculators would cost 275 in total