To prepare for a lab experiment, Ted is making a solution that uses two types of concentrations of HCI ( hydro boric acid) 80 ml of 50% HCI solution, and 120 mlL of 20% HCI solution. What is the HCI concentration of the mixes solution

32%

Step-by-step explanation:

50% of the first solution is HCL, so it has

80 ml x 50% = 80 ml x 0.5 = 40 ml of HCL

Similarly the second solution has 20% of HCL, so

120 ml x 20% = 120 ml x 0.2 = 24 ml of HCL

The combined solution will have 40 ml + 24 ml = 64 ml of HCL.

The total volume of the 2 solutions is 80 ml + 120 ml = 200 ml.

We can now calculate the concentration of HCL in the mixed solution, by dividing the volume of HCL by the total volume of the solution,

64 ml / 200 ml = 0.32 = 32%

m=-16

step-by-step explanation:

she will sew have sewn five dresses   and be 1/3 done with the sixth one in an hour.

step-by-step explanation:

3/4 of an hour=45 mins

lucy makes 1 dress per 11.25 minutes

45 mins+11.25 mins=56.25 mins

60 mins- 56.25 mins=3.75 mins

3.75 mins is 1/3 of of 11.25 mins

therefore she the other 1/3 would be part of the hour and she will have sewn 5 dresses and begun the sixth.

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