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What will be the sum, if 4/6is added 15 times ? |
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Answer» 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. |
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