A farmer planned to plough a field by doing 120 hectares a day. After two days of work he increased his daily productivity by 25% and he finished the job two days ahead of schedule. What is the area of the field?
Answers:
A) 1420
B) 1430
C) 1450
D) 1440
E) 1460
First of all we will find the new daily productivity of the farmer in hectares per day: 25% of 120 hectares is 25100⋅120=30 hectares, therefore   120+30= 
<gadget id="calculator">  120+30</gadget>
<output>150</output>
150 hectares is the new daily productivity. Lets x be the planned number of days allotted for the job. Then the farm is 120⋅x hectares. On the other hand, we get the same area if we add 120⋅2 hectares to 150(x−4) hectares. Then we get the equation   120x=120⋅2+150(x−4)   x=12   So, the job was initially supposed to take 12 days, but actually the field was ploughed in  12 - 2= 
<gadget id="calculator"> 12 - 2</gadget>
<output>10</output>
10 days. The field's area is 120⋅12=1440 hectares.   Answer is 1440.
<result>D</result>
A farmer planned to plough a field by doing 120 hectares a day. After two days of work he increased his daily productivity by 25% and he finished the job two days ahead of schedule. What is the area of the field?