There are 1000 Times more people on earth right now than there was in 4,000 BCE. It's just 7billion divided by 7million.
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Solve for "x":
x + 4y = 24
x + 16 = 24
x = 8
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Solution: (8,4)</span>
3 + 2 = 4 + 1 is true
1 +2 = 3 + 3 and 0 + 3 = 3+1 is not true
Let us say the original price of taco before tip was x dollars.
Percentage of tip given =25 %
Amount of tip given = $2
Now we can say that 25 % of total amount = 2 dollars.
Making an equation,

Now we have to solve for x, so dividing both sides by 0.25,
x= 8
Answer : The original price of tacos before tip was $8.