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For the families having no electricity i...

For the families having no electricity in their house, a Panchayat samity of village Bakultala accepted a plan to offer electric connections, 1200 families in these village have no electric connection in their houses. In comparison to its previous years, it is possible to arrange electricity every year for 75% of the families having no electricity. Find the number of families without electricity after 2 years.

Text Solution

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At present the no. of families having no electric connections `=1200`
Every year the electric connectiion increases `=75%`
`:.` Every year the no of families having no electric connections decreases `=100%-75%=25%`
`:.` After 2 years the number of families having no electric connections will be
`1200xx(1-25/100)^(2)=1200xx(1-1/4)^(2)`
`=1200xx(3/4)^(2)`
`=1200xx(3xx3)/(4xx4)=675`
Hence the number of families without electricity after 2 years will be 675.
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