The product of three numbers in A.P. is 224, and the largest number is 7 times the smallest. Find the numbers.

Answer: The three numbers are 2, 8, and 14.

Step-by-step solution

Step 1: Represent the numbers in A.P.

Let the three numbers in an Arithmetic Progression (A.P.) be represented as a−da - d, aa, and a+da + d. Here, aa is the middle term and dd is the common difference.

Step 2: Formulate equations from given conditions

We are given two conditions: first, the product of the three numbers is 224. This gives us the equation (a−d)a(a+d)=224(a - d)a(a + d) = 224. Second, the largest number (a+da + d) is 7 times the smallest number (a−da - d), which gives us a+d=7(a−d)a + d = 7(a - d).

Step 3: Solve the second equation for 'a' in terms of 'd'

Let's simplify the second equation: a+d=7(a−d)a + d = 7(a - d). Distribute the 7 on the right side to get a+d=7a−7da + d = 7a - 7d. Rearranging the terms, we get 8d=6a8d = 6a, which simplifies to a=43da = \frac{4}{3}d.

Step 4: Substitute 'a' into the first equation and solve for 'd'

Now, substitute a=43da = \frac{4}{3}d into the product equation (a−d)a(a+d)=224(a - d)a(a + d) = 224. This simplifies to (13d)(43d)(73d)=224(\frac{1}{3}d)(\frac{4}{3}d)(\frac{7}{3}d) = 224. Multiplying these terms gives 2827d3=224\frac{28}{27}d^3 = 224. Solving for d3d^3, we get d3=216d^3 = 216. Taking the cube root, we find d=6d = 6.

Step 5: Find the value of 'a'

With d=6d = 6, we can find the value of aa using the relation a=43da = \frac{4}{3}d. Substituting d=6d=6, we get a=43(6)=8a = \frac{4}{3}(6) = 8.

Step 6: Determine the three numbers

Finally, substitute the values of a=8a=8 and d=6d=6 back into our expressions for the three numbers: a−da - d, aa, and a+da + d. This gives us 8−6=28 - 6 = 2, 88, and 8+6=148 + 6 = 14. So the three numbers are 2, 8, and 14.

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