Answer: a. x=4 b. x=17.5
Step-by-step explanation:
a. 5x/2+1=11
subtract 1 from both sides : 5x/2=10
multiply both sides by 2 : 5x=20
divide both sides by 4 : x=4
b. 2x/7-3=2
add 3 to both sides : 2x/7=5
multiply both sides by 7 : 2x=35
divide both sides by 2 : x=17.5
You would need exactly 9 correct questions to get a 50%.
We can find this by multiplying the total number of questions by the percentage we are looking for.
18*50% = 9
4
5x - 4 = 16
Add four to both sides
5x = 20
Divide both sides by 5
x = 4
Answer:
Explanation:
<u />
<u>1. First find the density of your chain</u>
- Volume = displaced water volume
= Volume of Final level of water - initial level of water
= 20 ml - 15 ml = 5 ml
- Density = 66.7g / 5 ml = 13.34 g/ml
<u />
<u>2. Second, write the denisty of the chain as the weighted average of the densities of the other metals:</u>
Mass of gold × density of gold + mass of other metals × density of other metals, all divided by the mass of the chain.
Calling x the amount of gold, then the amount of other metals is 66.7 - x:



Then, there are 26.47 grams of gold in 66.7 grams of chain, which yields a percentage of:
- (26.47 / 66.7) × 100 = 39.7%
Answer:
(5(x-1))/3x
Step-by-step explanation: