Answer:
3 gallons
Step-by-step explanation:
Let
x ----> the amount of pure acid (100% solution) in gallons
Remember that



we know that

solve for x


therefore
3 gallons of pure acid should be mixed with 3 gallons of a 20% acid solution in order to get a 60% acid solution
Answer:
you are right
Step-by-step explanation:
To write 8.57 as a fraction you have to write 8.57 as numerator and put 1 as the denominator. Now you multiply numerator and denominator by 10 as long as you get in numerator the whole number.
8.57 = 8.57/1 = 85.7/10 = 857/100
And finally we have:
8.57 as a fraction equals 857/100
For #7 - part a: greatest common factor (GCF) is 5.
Part b: cross out everything BUT 10 & 20.
The final probability is the weighted average of the playing probabilities calculated over the possible weather options:
P(john practices cello; given that it rains) * P(it rains) +
P(john practices cello; given that it does not rain) * P(it does not rain) =
0.6 * 0.7 + 0.4 * 0.3 = 0.54
The probability is 54%