Answer:
6 2/3 mL
Step-by-step explanation:
Multiply thru by 100 to get:
1000 + 60x = 30*40 + 30x
30x = 200
x = 6 2/3 mL (amt. of 60% solution needed in the mixture)
3x² - 7x - 8 = 0
We're asked about square roots so we won't try to factor; we'll go right for the quadratic formula,
x = ( 7 ± √(7² - 4(3)(-8)) )/(2(3)) = (7 ± √(49+96))/6 = 7/6 ± √145/6
145 = 5×29, so no square factors. The positive difference is
d = (7/6 + √145/6) - (7/6 - √145/6) = 2√145/6 = √145/3
so m=145, n=3 for a sum of
Answer: 148
Answer:
A = 250(1 + 0.016)^0.75.
Step-by-step explanation:
9 months = 0.75 years
So A = 250(1 + 0.016)^0.75.
Answer: 25 grapefruits
Step-by-step explanation:
They buy grapefruit at a price of 5 per dollar. This means that the price per grapefruit is:
= 1 / 5
= $0.20 per grapefruit.
They then sell at a price of 5 per $3. The selling price per grapefruit is:
= 3 / 5
= $0.60
The profit per grapefruit is:
= 0.60 - 0.20
= $0.40
In order to make a profit of $10, they should sell:
= 10 / 0.4
= 25 grapefruits
