Question

b. If the selling price of an article is Rs 800 when it is sold at 25% profit, find its cost price.

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Answer 1

Step-by-step explanation:

a)3^x+3^(x+1)=324

=3^x+3^x×3^1=324

=3^x{1+3}=3×3×3×3×4

=3^x{4}={3^4}×{4}

=3^x=3^4

={x=4}

b)Cost price=c.p, Selling price=s.p

c.p+25%(c.p)=s.p

c.p+(25/100)(c.p)=800®

c.p(1+1/4)=800®

c.p=800®÷{(4+1)/4}

c.p=800®×(4/5)

c.p=160×4

c.p=640®