Two A.P.s have the same first term. The common difference of the first A.P. is -3 and of the second A.P. is -5. The difference of the 6th6^{th} term of the second A.P. from that of the first A.P. is :

Answer: 10

Step-by-step solution

Step 1: Define the terms of an A.P.

We start by recalling the formula for the nthn^{th} term of an arithmetic progression (A.P.), where ana_n is the nthn^{th} term, aa is the first term, and dd is the common difference.

Step 2: Express the 6th terms for both A.P.s

Let aa be the common first term for both A.P.s. For the first A.P., the common difference is d1=−3d_1 = -3. For the second A.P., the common difference is d2=−5d_2 = -5. We substitute these values into the formula to find the 6th6^{th} term for each A.P.

Step 3: Calculate the difference between the 6th terms

The problem asks for the difference of the 6th6^{th} term of the second A.P. from that of the first A.P., which means we need to calculate a1,6−a2,6a_{1{,}6} - a_{2{,}6}. We substitute the expressions we found for each 6th6^{th} term.

Step 4: Simplify the expression

We simplify the expression by distributing the negative sign and combining like terms. The first term aa cancels out, leaving us with the final difference.

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