A Plumber can be paid according to the following schemes: In the first

1.	A Plumber can be paid according to the following schemes: In the first scheme he will be paid Rs. 500 plus Rs.70 per hour, and in the second scheme he will be paid Rs. 120 per hour. If he works x hours, then for what value of x does the first scheme give better wages?
Answer» I scheme with x hr 500 + (x - 1) 70 = 500 + 70x – 70 = 430 + 70x II scheme with x hours 120x Here I > II ⇒ 430 + 70x > 120x ⇒ 120x – 70x < 430 50x < 430 50x/50 < 430/50 x < 8.6 (i.e.) when x is less than 9 hrs the first scheme gives better wages.

A Plumber can be paid according to the following schemes: In the first scheme he will be paid Rs. 500 plus Rs.70 per hour, and in the second scheme he will be paid Rs. 120 per hour. If he works x hours, then for what value of x does the first scheme give better wages?

Answer»

I scheme with x hr

500 + (x - 1) 70 = 500 + 70x – 70

= 430 + 70x

II scheme with x hours

120x

Here I > II

⇒ 430 + 70x > 120x

⇒ 120x – 70x < 430

50x < 430

50x/50 < 430/50

x < 8.6 (i.e.) when x is less than 9 hrs the first scheme gives better wages.