Answer:
Step-by-step explanation:
You can split the coins into 3 groups, each of them has 3 coins. Weigh group 1 vs group 2, if one is lighter, that group has the fake coin. If both groups weigh the same, then group 3 has the fake coin.
Continue to split the group that has the fake coin into 3 groups, each group has 1 coin. Now apply the same procedure and we can identify the fake coin.
Total of scale usage is 2
b) if you have 
coins then you can apply the same approach and find the fake coin with just n steps. By splitting up to 3 groups each step, after each step you should be able to narrow down your suspected coin by 3 times.
Step 1: you narrow down to group of 
coins
Step 2: you narrow down to group of 
coins
Step 3: you narrow down to group of 
coins
...
Step n: Step 1: you narrow down to group of 
coin
Okay, tu no tienes un Facebook...tienes una pregunta?
<h3>
Answer: a < 14 (Choice B)</h3>
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Explanation:
Add 4 to both sides
a-4 < 10
a-4+4 < 10+4
a < 14
The reason why we add 4 to both sides is to undo the "minus 4" that's happening to the variable.
Answer:
14 gel pens/minute
Step-by-step explanation:
divide the amount by time.
210/15 = 14
Answer:
m∠R=76°
Step-by-step explanation:
∠STR=∠RST=(2x+2)° (base angles of isos triangle)
2(2x+2)+(3x+1)=180 (angle sum of triangle)
4x+4+3x+1=180
7x+5=180
7x=180-5
=175
x=175÷7
=25
Hence, m∠R = (3x+1)°
= [3(25)+1]°
= (75+1)°
= 76°
