Answer:
222 mL
Step-by-step explanation:
okay so lets multply them lets call the quantity of hydrocloric acid x
so 61x+ 21(277.5-x)= 53*277.5
61x+ 21*277.5-21x= 53*277.5
40x=(53-21)(277.5)
40x= (32)(277.5)
x= 222 mL
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