Question

What will be the sum, if 4/6
is added 15 times ?

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Answer 1

Answer:

4 is added to the number, then algebraically, this can be expressed as: n + 4.

If this sum is multiplied by 3, then, algebraically, we can express this as:

3(n + 4). If this product is, in turn, equal to 30, then we can write the following equation and solve for n:

3(n + 4) = 30

To solve for n, we need to isolate n on the left side of the above equation, and we begin doing this by dividing both sides of the equation by 3 as follows:

[3(n + 4)]/3 = 30/3

(3/3)(n + 4) = 10

(1)(n + 4) = 10

n + 4 = 10

Now, we finish isolating n on the left, thus solving for n, by subtracting 4 from both sides of the equation:

n + 4 - 4 = 10 - 4

n + 0 = 6

n = 6

CHECK:

Replacing n with 6 in the original equation, we get:

3(n + 4) = 30

3(6 + 4) = 30

3(10) = 30

30 = 30

Therefore, n = 6 is indeed the desired, unknown number.