Arithmetic Progressions

The value of the expression
1 - 6 + 2 - 7 + 3 - 8 + ... to 100 terms

Two persons Anil and Happy joined D. W. Associates. Anil
and Happy started with an initial salary of Rs. 50000
and Rs. 64000 respectively with annual increment of Rs.
2500 and Rs. 2000 each respectively. In which year will
Anil start earning more salary than Happy ?

A number 15 is divided into three parts which are in AP
and sum of their squares is 83. The smallest part is

A man receives Rs. 60 for the first week and Rs. 3 more
each week than the preceeding week. How much does he
earns by the 20th week ?

The first term of an arithmetic progression is unity and
the common difference is 4. Which of the following will
be a term of this AP ?

A man saves Rs. 400 more each years than he did the
year before. If he saves Rs. 2000 in the first year after
how many years will his saving be more than Rs. 100000
altogether ?