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3 years ago

HELPP ME PLZ WILLING TO SEND MONEY! It’s urgent

Mathematics

2 answers:

BaLLatris [955]3 years ago

8 0

Answer:

Devon needs to add 60 mL of 5% acid solution and 30 mL of 20% acid solution

Step-by-step explanation:

It knows acid and water concentration for every solution. 2 equations are proposed because there are two unknowns. V1= volume 5%acid and V2 =volume 20% acid

Acid V1(0.05)+V2(0.2)=90mL(0.1)

Water V1(0.95)+V2(0.8)=90mL(0.9)

Clearing V1 from acid equation having to: V1=180-4V2

Replacing V1 in the water equation having to: (180-4V2)(095)+V2(0.8)=81

Clearing V2 = 30mL

Replacing in water equation V1(0.05)+30(0.2)=9 So, V1=60mL

ExtremeBDS [4]3 years ago

7 0

Answer:

I think it would be 5 and 5 of each solution

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Snezhnost [94]

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You want to find

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$\mathbb P\left(36\displaystyle\sum_{i=1}^{36}\frac{X_i}{36}>1000\right)=\mathbb P\left(\overline X>\dfrac{1000}{36}\right)$

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5 0

3 years ago

Use a model to divide. 1 ÷ 1/5

arlik [135]

This is the answer to the question

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3 years ago

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balandron [24]

Answer:

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Step-by-step explanation:

x = 2:

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Dmitrij [34]

Step-by-step explanation:

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