A set of exam marks has mean 70, median 65, inter-quartile range 25 and standard deviation 15 marks. It is decided to subtract 10 from all the marks. For the new set of marks,
i) what is the new mean?
ii) what is the new median?
I
iii) what is the new inter-quartile range?
iv) what is the new standard deviation?

The usa today reports that the average expenditure on valentine's day is $100.89. do male and female consumers differ in the amounts they spend? the average expenditure in a sample survey of 47 male consumers was $135.67, and the average expenditure in a sample survey of 38 female consumers was $68.64. based on past surveys, the standard deviation for male consumers is assumed to be $34, and the standard deviation for female consumers is assumed to be $17.