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If the price of lettuce goes down 10cents per kilo, one will be able to get 3 kilos more
lettuce with P3.60 than was possible at the lower price. What was the lower price?
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Let x be the lower price.
Then the higher price was (x+0.10).
From the condition, you have this equation
- = 3
To simplify, divide both sides by 3
- = 1. (1)
Now you can guess the answer MENTALLY: x = 0.30.
CHECK. - = 4 - 3 = 1. ! Correct !
Solved.
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Alternatively, instead of guessing, you may solve equation (1) algebraically,
reducing it to a quadratic equation.