Erika calculated that she would spend $115 on school supplies this year. she actually spent $82.50 on school supplies. what is erika's percent of error?

a: 28.3%

b: 2.8%

c: 39.4%

d: 32.5%

Percentage error is calculated by

Percentage error = (estimate-real)/real*100%=(115-82.5)/82.5*100%=28.26%

An over-estimate gives a positive error percent, and an underestimate gives a negative error.

Also, dividing by the real value makes it possible to have more than 100% error.

For example, if real cost is $50, and estimated cost is $150, then error percent is (150-50)/50*100%=200%!

C: 39.4%

Step-by-step explanation:

The formula to calculate the percent error is given by :-

Given: The estimated amount = $115

The actual amount = $ 82.50

Now,  the percent of error will be given by :-

  the correct choice is marked

step-by-step explanation:

the first two graphs show multiple turning points. the last graphs matches the description in every detail.

answer: the proof is mentioned below.

step-by-step explanation:

since, given:   lines bc = ef

prove:   lines ac > ef

          statements                                           reason

1. bc=ef                                           1. given

2. ac= ab+bc                                 2. because b is the point between the  

                                                            line segment ac

3.   ac > bc                                       3. because if a line segment is equal to

                                                          the sum of two line segments then it is

                                                          always greater then each of these

                                                          individual line segments

4. ac > ef                                         4. by equality property.