Answer:
105 cc of 7% solution
245 cc of 17% solution
Step-by-step explanation:
If x = volume of 7% solution, and y = volume of 17% solution, then:
x + y = 350
0.07x + 0.17y = 0.14(350)
Solve with substitution:
0.07x + 0.17(350 − x) = 0.14(350)
0.07x + 59.5 − 0.17x = 49
10.5 = 0.10x
x = 105
y = 245
No, its D
Just look at the rounds mentioned and subtract the scores from higher round with lower round.
Look at A: round 2 score - round 1 score = -2?
-3 -1 = -4 change, not -2 change so it is wrong
Look at B: round 3 score - round 1 score =-1?
-2-1 =-3 change, not -1 change so it is wrong
Look at C: round 3 score - round 2 score =-1?
-2 -(-3) = 1 change, not -1 change so it is wrong
Look at D: round 3 score - round 1 score =-3?
-2-1 = -3 change, matches with -3 so it is correct.
*Given
Money of Phoebe - 3 times as much as Andy
Money of Andy - 2 times as much as Polly
Total money of Phoebe, - £270
Andy and Polly
*Solution
Let
B - Phoebe's money
A - Andy's money
L - Polly's money
1. The money of the Phoebe, Andy, and Polly, when added together would total £270. Thus,
B + A + L = £270 (EQUATION 1)
2. Phoebe has three times as much money as Andy and this is expressed as
B = 3A
3. Andy has twice as much money as Polly and this is expressed as
A = 2L (EQUATION 2)
4. This means that Phoebe has ____ as much money as Polly,
B = 3A
B = 3 x (2L)
B = 6L (EQUATION 3)
This step allows us to eliminate the variables B and A in EQUATION 1 by expressing the equation in terms of Polly's money only.
5. Substituting B with 6L, and A with 2L, EQUATION 1 becomes,
6L + 2L + L = £270
9L = £270
L = £30
So, Polly has £30.
6. Substituting L into EQUATIONS 2 and 3 would give us the values for Andy's money and Phoebe's money, respectively.
A = 2L
A = 2(£30)
A = £60
Andy has £60
B = 6L
B = 6(£30)
B = £180
Phoebe has £180
Therefore, Polly's money is £30, Andy's is £60, and Phoebe's is £180.
Answer:
9
Step-by-step explanation:
Total initially in bookstore = 45
Sold 13copies, remaining copies = 45-13= 32
Sold 23 copies again, remaining copies = 32-23 = 9
Copies left = 9
