Question

Through the publicity of road safety programmes the street accident in a state has

been decreased by 10% in comparison to its previous year. In the present year if the

number of street accident be 2916, then calculate the number of street accidents that

had been in the state 3 years before.

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Answer 1

Answer:

Given :-

• Through the publicity of road safety programmes the street accident in a state has been decreased by 10% in comparison to its previous year. In the present year if the number of street accident be 2916.

Find Out :-

• then calculate had been in the state 3 years before.

Solution :-

Let, the number of street accidents 3 years

before in the district be x

∴ At present the number of street accidents in that district

$\Rightarrow$$x\bigg(1 - \dfrac{10}{100}\bigg)^{3}$

By the condition,

$\Rightarrow$$x\bigg(1 - \dfrac{10}{100}\bigg)^{3} = 2916$

$\Rightarrow$$x\times \dfrac{90}{100}\times \dfrac{90}{100}\times \dfrac{90}{100} = 2916$

$\Rightarrow$$x = \dfrac{2916\times{100}\times{100}\times{100}}{90 \times 90\times 90}$

$\Rightarrow$$x = \dfrac{2926000000}{729000}$

$\Rightarrow$ x = 4000

∴ The calculate had been in the state 3 years before is 4000.