The salary of a man is increased by 18% annually. If his present salary is 345,000, what was it a year ago?​

$292,372.88

Step-by-step explanation:

Let's say we want to increase some number x by 18%. We know we can't just multiply x by 18% since , which doesn't make sense if we are trying to increase x. Instead, we must multiply by 118%. This is because we want to add 18% of x back onto x. This is exactly like saying , since that expression is equal to .

Now, let's say that some number y is equal to our number x that was increased by 18%. Then, we know that from our equation above. If we solve this equation for x, we find that .

Now, notice that in this equation, y could represent the man's salary this year, and x could represent his salary last year. This is because his salary increases by 18% annually, so y is simply his last year's salary, x, increased by 18% ().

Finally, we can easily just plug in our numbers for y and x in our equation that's solved for x: , and we find our answer.

step-by-step explanation :

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