Question 1011827
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-10+5+20+35+50 = 100, is an arithmetic series with 1st term -10
 and common difference 15.

-8+6+20+34+48 = 100, is an arithmetic series with 1st term -8
 and common difference 14.

-6+7+20+33+46 = 100, is an arithmetic series with 1st term -6
 and common difference 13.

-4+8+20+32+44 = 100, is an arithmetic series with 1st term -4
 and common difference 12.

-2+9+20+31+42 = 100, is an arithmetic series with 1st term -2
 and common difference 11.

0+10+20+30+40 = 100, is an arithmetic series with 1st term 0
 and common difference 10.

2+11+20+29+38 = 100, is an arithmetic series with 1st term 2
 and common difference 9.

4+12+20+28+36 = 100, is an arithmetic series with 1st term 4
 and common difference 8.

6+13+20+27+34 = 100, is an arithmetic series with 1st term 6
 and common difference 7.

8+14+20+26+32 = 100, is an arithmetic series with 1st term 8
 and common difference 6.

10+15+20+25+30 = 100, is an arithmetic series with 1st term 10
 and common difference 5.

12+16+20+24+28 = 100, is an arithmetic series with 1st term 12
 and common difference 4.

14+17+20+23+26 = 100, is an arithmetic series with 1st term 14
 and common difference 3.

16+18+20+22+24 = 100, is an arithmetic series with 1st term 16
 and common difference 2.

18+19+20+21+22 = 100, is an arithmetic series with 1st term 18
 and common difference 1.

20+20+20+20+20 = 100, is an arithmetic series with 1st term 20
 and common difference 0.

22+21+20+19+18 = 100, is an arithmetic series with 1st term 22
 and common difference -1.

24+22+20+18+16 = 100, is an arithmetic series with 1st term 24
 and common difference -2.

26+23+20+17+14 = 100, is an arithmetic series with 1st term 26
 and common difference -3.

28+24+20+16+12 = 100, is an arithmetic series with 1st term 28
 and common difference -4.

30+25+20+15+10 = 100, is an arithmetic series with 1st term 30
 and common difference -5.

Edwin</pre>