A rectangular plot of size 18*8 m^2 has to be digged upto 8 m. depth. Cost of work increases conti

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15 Mar 2010 Rectangular Plot

A rectangular plot of size 18*8 m^2 has to be digged upto 8 m. depth. Cost of work increases continuously
from top to bottom. It starts from 10 rupee per cubic meter at top to 60 rupee per cubic meter at bottom.
Cost of complete work is ?

OPtion

1) 30720 rupee
2) 11520 rupee
3) 69120 rupee
4) 8640 rupee
5) 3840 rupee
6) 1440 rupee
7) 640 rupee
8) 40320 rupee
9) 34560 rupee
10) 5760 rupee

Solution

Total volume of digged earth = 18*8*8 = 1152 m3
Average cost of work = (10 + 60)/2 = 35 rupee per cubic meter
Total cost of work = 1152 * 35 = 40320 rupee

Correct Option: 8 Best Solution (13)

Pargat Pal Singh   14 years AGO

Cost of work increases continuously
from top to bottom. It starts from 10 rupee per cubic meter at top to 60 rupee per cubic meter at bottom.
Average cost per cubic Mtr = 10+(60-10)/2= Rs. 35

Total cost = 144*8*35 = Rs 40320

Like? Yes (1) | No   

S. Singh   14 years AGO

Average cost of work per Cubic Mtr = 10+(60-10)/2= 35 Rs per Cubic Mtr

Total cost = 18*8*8*35 = Rs. 40320 .... option 8

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Dr.Dipin Singh   14 years AGO

considering the rising cost 10 Rs per c Mtr to 60 Rs per CM from 0 M to 8 M, the average cost can be found by taking the area under graph (0,0), (0,10)(8,0) , 8,60) and taking average cost per Cubic Mtr by diving it with 8, we get average cost of 35 Rs per cubic mtr.

The total cost will be 18*8*8*35 = Rs 40320.

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HARMEET KAUR   14 years AGO

Average cost of work = 10+(60-10)/2= 35 Rs per Cubic Mtr

Total cost = 18*8*8*35 = 40320 Rupee

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Saranjit Singh   14 years AGO

Average cost of work = 10+(60-10)/2= 35 Rs per Cubic Mtr

Total cost = Total vol * Rate = 18*8*8*35 = 40320

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Neha Bhatia   14 years AGO

it will 40320rs

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Dr. Divya   14 years AGO

Average cost per Cubic metre = 280/8= 35

Total cost = 18*8*8*35 = 40320

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Bawa   14 years AGO

Average cost per cubic mtr = 10 + (60-10)/2= 10+25 = Rs 35.

Total cost = 144*8*35 = 40320 Rs.

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Bimal   14 years AGO

Average cost per Cubic Mtr = (10+60)/2= 35 rs

total cost = 18*8*8*35 = Rs. 40320

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nitin sakhala   14 years AGO

40320 is the required solution
by integrating 0 to 8 expression 144(6.25x+10)dx

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sivakumar   14 years AGO

=18*8*8*(10+60)/2= 40320 rupee

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kewal   14 years AGO

Here the cost per cubic Mtr is varying linearly with depth.
Average cost wil be 10+ (Total difference in cost / 2) = 10+50/2= 35 Rs per cubic mtr

total cost = 18*8*8*35 = 40320 Rs

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Dundi   14 years AGO

18*8*8*35=40320

Like? Yes (1) | No