Archive
14th of September 2015
Mathematics
Q:

if the cost of rice reduces by 20% a housewife can buy 5kg more of rice at rs.320. find the original price.

Harsh K - ICSE - Class IX

Friday, September 11, 2015 at 23:04:PM

A:

Hi Harsh

Let space Rs. space straight x divided by kg space be space the space cost space of space the space rice.  therefore Rice space can space be space purchased space in space Rs. space 320 space at space price space Rs. space straight x divided by kg space equals 320 over straight x  The space cost space of space rice space reduced space by space 20 percent sign New space cost space of space rice space is space equals space straight x minus space 20 over 100 straight x space equals space 0.8 straight x  therefore Rice space can space be space purchased space in space Rs. space 320 space at space price space Rs. space 0.8 space straight x divided by kg space equals fraction numerator 320 over denominator 0.8 straight x end fraction  Housewife space can space buy space 5 space kg space more space rice space at space discounted space rate therefore fraction numerator 320 over denominator 0.8 straight x end fraction minus 320 over straight x equals 5 5 straight x space equals space 400 space minus space 320 5 straight x space equals space 80 straight x space equals space 16  So space the space original space price space of space the space rice space is space Rs. space 16.

Monday, September 14, 2015 at 13:13:PM