In a mango grove, the number of trees planted in a row was equal to the total number of rows in the grove. If the number of rows is doubled, and the number of trees in each row is reduced by 5, then the total number of trees will increase by 375. Find the total number of trees planted originally.

Asked by joybasu274 | 13th Jan, 2018, 10:35: AM

Expert Answer:

begin mathsize 16px style Let space the space number space of space trees space planted space be space straight x.
According space to space the space question comma
total space number space of space trees space planted equals x cross times x equals straight x squared
If space the space number space of space rows space is space doubled space then space number space of space rows space equals space 2 straight x
and space each space row space is space reduced space by space 5 space then space total space number space of space rows space equals space straight x minus 5
Total space number space of space trees space will space increase space by space 375.
rightwards double arrow 2 straight x open parentheses straight x minus 5 close parentheses equals straight x squared plus 375
rightwards double arrow 2 straight x squared minus 10 straight x equals straight x squared plus 375
rightwards double arrow straight x squared minus 10 straight x minus 375 equals 0
rightwards double arrow open parentheses straight x minus 25 close parentheses open parentheses straight x plus 15 close parentheses equals 0
rightwards double arrow straight x equals 25 space as space straight x not equal to negative 15
Total space number space of space trees space planted space originally space was space 25.
end style

Answered by Sneha shidid | 15th Jan, 2018, 09:41: AM