In $2009$,the food production was $5.5$ million tonnes and in $2010$,the production was $4.4$ million tonnes. Find out the percentage decrease in food production in these two years?

If $60 \%$ of the students in a school are boys and the number of girls is $812$,how many boys are there in the school?

In an election between two candidates,one got $55 \%$ of the total valid votes,and $20 \%$ of the total votes were invalid. If the total number of votes was $7500$,what was the number of valid votes that the other candidate received?

Dinesh's monthly income is four times Suresh's monthly income. Suresh's monthly income is $20\%$ more than Jyoti's monthly income. Jyoti's monthly income is $₹ 22,000$. What is Dinesh's monthly income?

$1200$ boys and $650$ girls appeared in an examination. If $70 \%$ of boys and $40 \%$ of girls failed,find the approximate percentage of passed students.

The value of a machine is $Rs$ $6250$. It decreases by $10 \%$ during the first year,$20 \%$ during the second year,and $30 \%$ during the third year. What will be the value of the machine after $3$ years?