It's tricky but anyone can figure it out. In its first sentence, the problem gives us that a = 3/4b + 15.
Then it tells us that the two integers together are more than 49 and they want to know about the least value of the two, which means that the next whole number is requested, which is 50. So, a+b = 50. So now we have two equations with exactly the same two variables in play, which is the stuff of simultaneous equations. We solve them against each other by first making them as compatible as possible. The first equation will look more like the second if we move the b over to the left side. That means a - 3/4b = 15. Since the variable "a" matches up, we don't have to do anything else to modify the equations. The variable "a" will drop out as soon as we subtract one equation from the other. Then we can solve for b and plug in that result to solve for a.
a + b = 50 Now subtract the second equation below it
a - 3/4b = 15
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1.75b = 35 Now divide both sides by 1.75 to get:
b = 20
Therefore, 3/4b = 15.
We know from the first equation that it takes another 15 to get to a, so 15 + 15 = 30, which means a = 30.
