The sum of all two digit numbers each of which leaves remainder 3 when divided by 5 is

Two digit numbers which leaves remainder 3 when divide by 5 are13,18,−−−−98

From the formed AP, first term a=13, common difference d=5 and An=98

using general term of an AP form

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An=a+(n−1)d

98=13+(n−1)5

85=(n−1)5

17+1=n

∴n=18

In total we have 18 such numbers

So, S = 18/2(2×13+17×5)=999