<PRE><B>Question 809872</B>
The weight of calcium hydroxide is {{{ .17*250 = 42.5 }}} kg
The weight of sodium hydroxide is {{{ .11*250 = 27.5 }}} kg
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In the new mixture, the weight of calcium hydroxide is {{{ .19*250 = 47.5 }}} kg
In the new mixture, the weight of sodium hydroxide is {{{ .19*250 = 47.5 }}} kg
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{{{ 47.5 - 42.5 = 5 }}} kg
{{{ 47.5 - 27.5 = 20 }}} kg
 5 kg of  calcium hydroxide must be added
20 kg of sodium hydroxide must be added
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