Answer:
84 ounces of pure gold
Step-by-step explanation:
Jess has 60 ounces of an alloy that is 40% gold. How many ounces of pure gold must be added to this alloy to create a new alloy that is 75% gold?
Pure gold = 100% gold
Let the number of ounces of pure gold = x
Hence, we have the equation
40% × 60 ounces + 100%× x ounces = 75%(60 + x)ounces
= 0.4 × 60 + 1x = 0.75(60 + x)
= 24 + x = 45 + 0.75x
Collect like terms
x - 0.75x = 45 - 24
0.25x = 21
x = 21/0.25
x = 84 ounces
Therefore, we need 84 ounces of pure gold
t = time to hike up the hill
3-t is the time to hike down the hill
so 4t = 6(3-t)
4t = 18-6t
10t = 18
t = 18/10 = 1.8 hours to hike up the hill
1.8 hours = 1 hour 48 minutes

let's factorise :
now, there are two cases :
case 1 :
case 2 :
Answer:
Step-by-step explanation:
100 bro
Answer:
<h2>
$83.2</h2>
Step-by-step explanation:
If the CPI for 1930 was 16.7, while for 1939 it was 13.9, the change in CPI will be 16.7 - 13.9 = 2.8. The amount lost within the year 19.30 to 1939 if the cost of the item in 1930 is $100 will be expressed as;
= 2.8/16.7 * 100
= 280/16.7
= $16.8
The amount the item would have cost in 1939 will be $100 - $16.8 = $83.2