What is the single equivalent discount to a series of successive discount of 30% 10% and 5%?

Answer

Verified

Hint: First, we will assume any number on which we will find two successive discounts given. So, we will take the number to be 100. Then by using the formula \[\left( x-discount\%\cdot x \right)\] where x is the number we assumed, we will find first for 20% and then taking x to be the answer we got , on 10%. At last, we will use the same formula where we have to find a discount%. Thus, on solving we will get the answer.

Complete step-by-step answer:

Here, we will first assume any number of which will find the two successive discounts. So, we will assume that number to be 100. Now, 20% discount on 100 will be given as \[\left( x-discount\%\cdot x \right)\] where x is 100 in this case. So, using this we will get as\[\left( 100-\dfrac{20}{100}\cdot 100 \right)=100-20=80\] Now, again we will find a 10% discount on 80. So, we will get as\[\left( 80-\dfrac{10}{100}\cdot 80 \right)=80-8=72\] Thus, successive discounts i.e. 20% and 10% on 100 is 72. So, now we will see how much percent of 100 is equal to 72. So, here the formula used will be \[\left( x-discount\%\cdot x \right)\] where we have to find a discount%. So, we will get as \[100-\dfrac{y}{100}100=72\] On solving, we will get as\[100-72=y\] \[28=y\] Thus, the answer is 28%. Option (a) is the correct answer.

Note: Another method to find successive discounts is by using the formula \[\left( x+y-\dfrac{xy}{100} \right)\%\] where x, y are discount values. So, by putting values and solving them we get an equation as \[\left( 20+10-\dfrac{20\cdot 10}{100} \right)\%\] . On further solving, we get as \[\left( 30-2 \right)\%=28\%\] . Thus, we will get the same answer.

Uh-Oh! That’s all you get for now.

We would love to personalise your learning journey. Sign Up to explore more.

Skip for now

Uh-Oh! That’s all you get for now.

We would love to personalise your learning journey. Sign Up to explore more.

Skip for now

SSC GD Constable Final Result Out on 7th November 2022 for 2021 cycle! A total of 25271 vacancies have been considered for allocation in the forces. SSC GD Constable 2022 Notification had been released on 27th October 2022. A total of 24,369 vacancies have been released for the recruitment of GD Constables in various departments like BSF, CRPF, CISF, etc. Candidates can apply for the exams between 27th October 2022 to 30th November 2022. Applicants must note that they can apply for this recruitment only through the official website. The SSC GD Constable Exam Pattern has also been changed. Candidates can check all the details below.