Answer: 14
Explanation:
Given: The total balance in the account = $200
Also the business assistant must leave more than $50 in the supply account.
Therefore, the maximum amount he can use to order boxes=
..(1)
Since the assistant needs to order x boxes of pens.
Cost of each box = $10.50
Therefore, cost of x boxes=10.50 x
From (1), we have the inequality
![10.50x\leq150\\\\\Rightarrow\ x\leq(150)/(10.50)\\\\\Rightarrow\ x\leq14.285\\\Rightarrow\ x=14....\text{[since 14 is the maximum whole number less than 14.285]}](https://img.qammunity.org/2018/formulas/mathematics/middle-school/cpvpt5zb4yztknurnkzeoxe36d66z7mc6i.png)
Hence, the business assistant can buy maximum 14 boxes of pens.