We have been given that a jeweler has 5 rings, each weighing 12 g, made of an alloy of 20% silver and 80% gold.
Upon melting all 5 rings, the weight of the material will be 12*5=60 grams.
We have been given that the alloy contains 20% silver and 80% gold. Further, let us assume that x grams of silver are added to the melted material so that it has 64% gold and 36% silver.
Therefore, we can set up an equation:

Therefore, we get an equation:


Therefore, 15 grams of silver must be added to the melted material in order to reduce the gold content to 64%.
Answer:
<h2>432 ft²</h2>
Step-by-step explanation:
The formula of an area of a trapezoid is:

<em>b₁, b₂</em><em> - bases</em>
<em>h</em><em> - height</em>
<em />
We have:
<em>b₁ = 20 ft, b₂ = 16 ft, h = 24 ft</em>
Substitute:

A.) First, you find the total sales. $2030 + $1540 + $1800 = $5370. Then, divide each with the total. The answer would be:
Lola: 203/537
Ahmed: 154/537
Tommy: 60/179
b.) Divide 100 by 3 for equal shares. Each person receives $33.3.
Answer:
6.2832 square units (rounded off to four decimal values)
Step-by-step explanation:
Area of a semicircle =
× π × r²
r (radius) = 2 units
For our semicircle the area =
× π × 2² = 6.28318530718 square units
Or 6.2832 square units (rounded off to four decimal values)
The second train will catch up with the first train in 1.6 hours