Answer:
The jar of chermical contains 66g of Zinc.
Step-by-step explanation:
The ratio of Zinc to Copper is 3 : 13
A jar of the chemical contains 286g of copper.
Let the mass of the Zinc be xg.
= 
x =
= 66g
So the jar of chemical contains 66g of Zinc.
Answer:D. 33.3%
Step-by-step explanation:
Answer:
B) 20.6 mi/hr
Step-by-step explanation:
To solve this, we need to first convert 40 meters to mile, then convert 4.35 seconds to hour, then solve by proportion.
converting 40 meters to mile;
1 mile = 1609.344 meter
x = 40 meters
1609.344x = 40
x = 40/1609.344
x =0.02485 mile
Then converting seconds to hour
1 hour = 3600 seconds
y = 4.35 seconds
3600 y = 4.35
y=4.35/3600
y =0.00121 hour
Using proportion to solve the question
Let n be the number he runs miles per hour
0.02485 mile = 0.00121 hour
n = 1 hour
cross-multiply
0.00121 n = 0.02485
Divide both-side by 0.00121
0.00121 n/0.00121 = 0.02485/0.00121
n ≈ 20.6 mile/hour
Therefore, he is running 20.6 mi/hr
Find a common denominator between the two (this case it would be 18) and bring the fractions up, so 10/9 would be 20/18, and 3/2 would be 27/18. Then, multiply across, and simplify to lowest terms.