Answer:
Metals which react with steam form the solid metal oxide and hydrogen gas.
In general, the more reactive the metal, the more rapid the reaction. Aluminium is unusual, because it is a reactive metal that does not react with water. Its surface forms a protective layer of aluminium oxide that keeps water away from the metal below.
The apparatus used to react a metal with steam and collect the gas produced is shown below.
Answer:
$9.50 = .25x
Step-by-step explanation:
38 quarters
Answer:
x = 14
Step-by-step explanation:
Answer:
An apple costs $2.25. A mango costs $1.25.
Step-by-step explanation:
Let a = price of 1 apple.
Let m = price of 1 mango.
Cameron:
4 apples + 7 mangoes ----> total $17.75
4a + 7m = 17.75
Gavin:
2 apples + 5 mangoes ----> total $10.75
2a + 5m = 10.75
We have a system of 2 equations in 2 unknowns.
4a + 7m = 17.75
2a + 5m = 10.75
We can use the elimination method to eliminate the variable <em>a</em>. Rewrite the first equation. Multiply both sides of the second equation by -2 and write below it. Then add the equations.
4a + 7m = 17.75
(+) -4a - 10m = -21.5
---------------------------------
-3m = -3.75
Divide both sides by -3.
m = 1.25
<em>A mango costs $1.25.</em>
Now we use the first equation and substitute 1.25 for <em>m</em> and solve for <em>a</em>.
4a + 7m = 17.75
4a + 7(1.25) = 17.75
4a + 8.75 = 17.75
4a = 9
a = 2.25
<em>An apple costs $2.25.</em>
Answer: An apple costs $2.25. A mango costs $1.25.
Step-by-step explanation:
We will learn how to solve proportion problems. We know, the first term (1st) and the fourth term (4th) of a proportion are called extreme terms or extremes, and the second term (2nd) and the third term (3rd) are called middle terms or means.
Therefore, in a proportion, product of extremes = product of middle terms
example
1. Check whether the two ratios form a proportion or not:
(i) 6 : 8 and 12 : 16; (ii) 24 : 28 and 36 : 48
Solution:
(i) 6 : 8 and 12 : 16
6 : 8 = 6/8 = 3/4
12 : 16 = 12/16 = 3/4
Thus, the ratios 6 : 8 and 12 : 16 are equal.
Therefore, they form a proportion.
