
Let,
- Mass of the steel be 108x
- Mass of the copper be 7x
- Then, Total mass = 108x + 7x = 115x
Given,
- Total mass of the coin = 230 mg
That means,
⇛ Total mass of the coin = 230 mg
⇛ 115x = 230 mg
⇛ x = 230 mg/115
⇛ x = 2 mg
Then,
- Mass of the steel = 108(2) = 216 mg
- Mass of the copper = 7(2) = 14 mg
☁️ ANSWER - 14 mg (Mass of copper)
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Answer:
Its the alternative C because as you can see the dots ar placed in the following coordinates(sorry for my English). The first dot is placed (1, 4) the second is placed (2, 6) the third is (3, 10) and last is (4, 12)
The formula of geometric sequence is expressed in the following manner:
an = a1 * r^(n-1) where r is the ratio and n is an integer.
Substituting, to find r
358.80 = <span>14 * r^(8)
r is equal to 1.5
hence,
</span><span>a19 = 14* 1.5^(19-1)
</span>a19 <span> ≈ 20,690.</span>