Error analysis
a student says that the perimeter of a rectangle with side lengths (2x-1)inches and 3x inches can be written as (10x-1) inches. because 2(2x-1) + 2(3x)=10x-1. explain why this statement is incorrect.

Aparticular telephone number is used to receive both voice calls and fax messages. suppose that 25% of the incoming calls involve fax messages, and consider a sample of 25 incoming calls. (a) what is the expected number of calls among the 25 that involve a fax message?

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

In a young single person's monthly budget, $150 is spent on food, $175 is spent on housing, and $175 is spend on other items. suppose you drew a circle graph to represent this information, what percent of the graph represents housing?