Question

“Donations to an annual fundraiser are 15% greater this year then last year. Last year, donations were 10% greater than a year before. The amount raised this year is $10,120. How much was raised 2 years ago?”

Answer 1

Answer:  Amount was raised 2 years ago was $8000.

Step-by-step explanation:

Since we have given that

Amount raised this year = $10120

According to question,

Donation were 10% greater than a year before .

Donation  were 15% greater that year than its previous year i.e. 2 years ago.

Let amount raised 2 years ago be x

So, it becomes,

$x\times \frac{115}{100}\times \frac{110}{100}=\ 10120\\\\x=10120\times \frac{100}{115}\times \frac{100}{110}\\\\x=\ 8000$

Hence, Amount was raised 2 years ago was $8000.

Answer 2

Answer: The amount raised 2 years ago was $8000.

Step-by-step explanation:

Since we have given that

The amount raised this year = $10120

Let the amount that was raised 2 years ago be 'x'.

There is increment this year than last year = 15%

There is increment last year than a year before = 10%

So, We need to find the value of x i.e. the original donation 2 years ago was:

So, According to question, our equation becomes

$x\times \dfrac{100+10}{100}\times \dfrac{100+15}{100}=10120\\\\x\times \dfrac{110}{100}\times \dfrac{115}{100}=10120\\\\x\times 1.1\times 1.15=10120\\\\x=\dfrac{10120}{1.1\times 1.15}=8000\\\\x=\ 8000$

Hence, the amount raised 2 years ago was $8000.