Question

Madhuri went to a supermarket. The price changes are as follows. The price of rice reduced by 5%, jam and fruits reduced by 8%, and oil and dal increased by 10%. Help Madhuri to find the changed price in the given table.

Item	Original price per kg(Rs.)	Changed price
Rice	30
Jam	100
Apples	280
Oil	120
Dal	80

Answer 1

Hint: Use the given reduction and increment percentage along with the given original prices to find the changed rate. For the reduction, find the change percent by subtracting the given reduction percent from 100 and for increment, find the change percent by adding the given increment percent from 100.

Complete step by step solution:
It is given that the price of rice reduced by 5%, jam and fruits reduced by 8%, and oil and dal increased by 10%.
We have to find the changed price for each item.
As we have given that the price of rice reduced by 5% and the original price of rice is Rs.30, so the changed price is the $\left( {100 - 5} \right) = 95$% of the original price.
$ \Rightarrow 95\% {\text{ of }}30$
We simplify the value:
$ \Rightarrow \dfrac{{95}}{{100}} \times 30$
$ \Rightarrow 28.5$
So, the changed price of the rice is Rs.$28.5$.
Similarly, we have given that the price of jam is reduced by $8\% $ and the original price of the jam is Rs.100, so the changed price is the \[\left( {100 - 8} \right) = 92\]% of the original price.
\[ \Rightarrow 92\% {\text{ of 100}}\]
We simplify the value:
\[ \Rightarrow \dfrac{{92}}{{100}} \times {\text{100}}\]
\[ \Rightarrow 92\]
So, the changed price of the jam is Rs.$92$.
We have also given that the price of an apple is reduced by $8\% $ and the original price of the apple is Rs280, so the changed price is the $\left( {100 - 8} \right) = 92$% of the original price.
\[ \Rightarrow 92\% {\text{ of 280}}\]
We simplify the value:
\[ \Rightarrow \dfrac{{92}}{{100}} \times 280\]
\[ \Rightarrow 257.6\]
So, the changed price of the apple is Rs.$257.6$.
We have also given that the price of oil has increased by $10\% $ and the original price of the oil is Rs.120, so the changed price is 110% of the original price.
\[ \Rightarrow 110\% {\text{ of 120}}\]
We simplify the value:
\[ \Rightarrow \dfrac{{110}}{{100}} \times {\text{120}}\]
\[ \Rightarrow 132\]
So, the changed price of the oil is Rs.$132$.
We have also given that the price of dal has increased by $10\% $ and the original price of the dal is Rs.80, so the changed price is 110% of the original price.
\[ \Rightarrow 110\% {\text{ of 80}}\]
We simplify the value:
\[ \Rightarrow \dfrac{{110}}{{100}} \times 80\]
\[ \Rightarrow 88\]
So, the changed price of the dal is Rs.$88$.
Hence, we have changed price shown in the table below:

Item	Original price per kg(Rs.)	Changed price
Rice	30	28.5
Jam	100	92
Apples	280	257.6
Oil	120	132
Dal	80	88

Note: We can also find the changed price by an alternate method.
For reduction: Original price – $\left( {\% {\text{ of original price}}} \right)$
For increment: Original price + $\left( {\% {\text{ of original price}}} \right)$
Rice: $30 - \left( {5\% {\text{ of 30}}} \right) = 30 - 1.5 = 28.5$
Jam: $100 - \left( {8\% {\text{ of 100}}} \right) = 100 - 8 = 92$
Apple: $280 - \left( {8\% {\text{ of 280}}} \right) = 280 - 22.4 = 257.6$
Oil: $120 + \left( {10\% {\text{ of 120}}} \right) = 120 + 12 = 132$
Dal: $80 + \left( {10\% {\text{ of 80}}} \right) = 80 + 8 = 88$