11. Bir aritmetik dizide ilk 15 terim toplamını bul- mak için kullanmamız gereken formül hangi şıkta doğru verilmiştir? \( \begin{array}{ll}\text { A) } \frac{15}{2} \cdot\left(a_{1}+a_{15}\right) & \text { B) } 15 \cdot\left(a_{1}+a_{15}\right) \\ \text { C) } 2.15 \cdot\left(a_{1}+a_{15}\right) & \text { D) } 2 \cdot 15 \cdot\left(a_{1}+a_{15}\right)\end{array} \) \( \begin{array}{ll}\text { E) } \frac{\left(a_{1}+a_{15}\right)}{2}\end{array} \)

How many cups are there in 48 oz?

4. Ariell has 36 chemistry books, 32 biology books and 28 physics books. She wishes to arrange the books in groups such that each group has the same number of each book without any book being lof out. Calculate the maximum number of books that can be found in each group. (3 marks)

A water tank has two pipes of different sizes to fill water. One pipe can fill \( \frac{1}{5} \) part of the tank in 1 hour and another pipe can fill \( \frac{1}{4} \) part in 1 hour. (i) If both the pipes are opened at a time, what parts of the tank would be filled in 2 hours? (ii) If the capacity of the tank is 10,000 litres, how much water would be filled in 2 hours?

Manny makes dinner using 1 box of pasta and 1 jar of sauce. If pasta is sold in packages of 6 boxes and sauce is sold in packag of 3 jars, what is the least number of dinners that Manny can \( m \) without any supplies leftover?

13. What multiple of 7 is also a factor of 7 ?