Best Answer

In absolute terms, the percentage decrease is:

percentage change = (new - old)/old × 100%

= (25 - 100)/100 × 100%

= -75 %

Being negative it means the change is a decrease of 75%


However, when the cost of money is taken into account it is higher - the buying power of 100 in 1970 was much more than the buying power of 100 in 2018 due to inflation.

I do not know the inflation figures for the 48 years from 1970 to 2018 - it will vary from country to country (and year to year), but if we assume an average of 5% per year (probably an under estimate), then:

100 after 48 years with average annual 5% inflation would cost 100 × (1 + 5/100)⁴⁸

percentage change = (25 - 100 × 1.05⁴⁸)/(100 × 1.05⁴⁸) × 100% ≈ -97.6 %

A decrease of about 97.6%

With inflation at about 7.177% prices double every 10 years; using this as inflation, the decrease is approx 99.1% - in other words they are almost giving the calculator away today.

User Avatar

Wiki User

6y ago
This answer is:
User Avatar

Add your answer:

Earn +20 pts
Q: In 1970 a desktop calculator sold for about 100.00. Today the same type of calculator sells for as little as 25.00. What is the percent of decrease in the cost of desktop calculators?
Write your answer...
Still have questions?
magnify glass
Related questions

The price of a TI-83 calculator dropped from 120 to 89. What is the percent of decrease?

It works out as a 25.83% decrease

Where are savings calculators found in stores?

In actuality, most stores don't sell specific savings calculators. Browsers can use sites like Percent Off Calculator, Bankrate, and Web Winder among others for this type of calculator, but a physical savings calculator is not sold in stores.

How do you decrease a number by a percent?

You can put the percent number over 100 and multiply it by the number you want to decrease, like 9% decrease from 100 would be 9/100 times 100... If you have a calculator, you can move the decimal place over to the right twice, and mulitply. So 9% would be 0.09.

What is the percent decrease from 96 percent to 84 percent?

12.5% decrease.

What is the percent decrease from 42 percent to 38 percent?

9.5238% decrease.

How do you convert a fraction into a percent on a calculator?

Not all calculators have a percent key. Simply do the following: Divide the top of the fraction (numerator) by the bottom (denominator) and multiply the result by one hundred. Example: Convert 7/20 into a percent. 7 divided by 20 is 0.35 Multiply by 100 Gives answer - 35%

What is the definition of percent of decrease?

the amount of decrease in a percent

what is the percent decrease of 300 to 240?

20 percent decrease.

What is the percent decrease from 80 to 64 percent?

20% decrease.

What is the percent decrease of 148 to 121?

148 to 121 is a percent decrease of 18.24%

What is the percent decrease from 14.00 to 9.00?

The percent decrease from 14 to 9 is 35.71.

What is the percent decrease of 765 to 153?

The percent decrease of 765 to 153 = 80%