Martin had m dollars initially. first, martin spent 1/3 of his money. then martin spent 3/4 of what was left. finally, martin spent another $20. write an expression in terms of m for the final amount of money that martin has. then write another equivalent expression. explain.

first he had M some unknown amount 

then he had 2/3 M since he spent 1/3 M

then he spent 3/4 of the (2/3 M) so he had 1/4 of the ( 2/3M) 

then he spent what was left $20 so $20 = 1/4 ( 2/3 M) now solve for M

and check by doing each step and figuring how much was spent and how much left.

another method

let us consider the left amount be Y and total now of M dollar be X

then

Y = amount of money Nartin has left 

Y = X - ( 1/3 ) ( X ) - ( 3/4 ) ( X - 1/3 X ) - 20 

Y = X - 1/3 X - 3/4 X + 3/12 X - 20 

Y = X - 4/12 X - 9/12 X + 3/12 X - 20 

Y = X - 10/12 X - 20 

Y = X - 5/6 X - 20 

Y = ( 1 / 6 ) ( X ) - 20 

hope it helped u buddy : )

y=mx+

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