In an Area Having Sandy Soil, 50 Small Trees of a Certain

question 4

Essay

In an area having sandy soil, 50 small trees of a certain type were planted, and another 50 trees were planted in an area having clay soil. Let X = the number of trees planted in sandy soil that survive 1 year and Y = the number of trees planted in clay soil that survive 1 year. If the probability that a tree planted in sandy soil will survive 1 year is .7 and the probability of 1-year survival in clay soil is .6, compute an approximation to $P ( - 6 \leq X - Y \leq 6 )$ (do not bother with the continuity correction).

---

Definitions:

Purchases Discounts

An allowance given by the seller to the buyer for early payment or for buying in large quantities.

Net Purchases

The total cost of goods bought for resale, after subtracting returns, allowances, and discounts.

Merchandise Inventory

Goods that a company holds for the purpose of selling to customers.

Payroll Tax Expense

Taxes imposed on employers or employees, and are usually calculated as a percentage of the salaries that employers pay their staff.