Aptitude =a positive aptitude./// i teach you arithmetic in very simple way but i sure you, you can solve it very efficiently

Methodology

Q:if the cost of rice is increase by 10%,and then the cost of rice is decrease by 10%.what's the overall profit /loss .
Ans: - (10*10/100)=-1
(minus sign indicate loss)
OR
SIMPLY{ IN THESE TYPES OF QUESTIONS ALWAYS LOSS IS HAPPENED, AND CALCULATED BY (square of profit /loss divided by 100)}.
OR
LET'S THE INITIAL COST OF SUGAR IS 100 RUPEES.
AFTER INCREASING 10%.
THE NEW COST IS 110 RUPEES.
NOW THE COST IS DECREASING BY10%,
(110-110*10%)=99.
LOSS=COST PRICE - SELLING PRICE.
LOSS=(100-99)=1RUPEES