Answer:
The ceiling is lower than 3 meters.
Step-by-step explanation:
In the above, the product is <em>less than</em> 3. In this case, it will not include 3 as a choice, as if it would, the would be used.
This means that x would be any number that is less than 3. The only choice that gives a choice that means less than by the terms definition is A) The ceiling is lower than 3 meters.
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48 kilograms of 15 % copper is combined with 72 kilograms of 75 % copper to create 120 kg of a 51% copper alloy
<em><u>Solution:</u></em>
Let "x" be the kilograms of 15 % copper
Then, (120 - x) be the kilograms of 75 % copper
Then, according to question,
"x" kilograms of 15 % copper is combined with (120 - x) kilograms of 75 % copper to create 120 kg of a 51% copper alloy
Thus we frame a equation as:
15 % of x + 75 % of (120 - x) = 51 % of 120
<em><u>Solve the equation for "x"</u></em>
Thus 48 kilograms of 15 % copper used
Then, (120 - x) = (120 - 48) = 72
Thus, 72 kilograms of 75 % copper is used