Answer:
How many days do you exercise in a week?
Step-by-step explanation:
The topic is students' weekly exercise so the question has to be about that. also, there are up to 7 days worth of data and there a 7 days in a week. so she most likely asked the question, "How many days do you exercise in a week?".
18 kg of 15% copper and 72 kg of 60% copper should be combined by the metalworker to create 90 kg of 51% copper alloy.
<u>Step-by-step explanation:</u>
Let x = kg of 15% copper alloy
Let y = kg of 60% copper alloy
Since we need to create 90 kg of alloy we know:
x + y = 90
51% of 90 kg = 45.9 kg of copper
So we're interested in creating 45.9 kg of copper
We need some amount of 15% copper and some amount of 60% copper to create 45.9 kg of copper:
0.15x + 0.60y = 45.9
but
x + y = 90
x= 90 - y
substituting that value in for x
0.15(90 - y) + 0.60y = 45.9
13.5 - 0.15y + 0.60y = 45.9
0.45y = 32.4
y = 72
Substituting this y value to solve for x gives:
x + y = 90
x= 90-72
x=18
Therefore, in order to create 90kg of 51% alloy, we'd need 18 kg of 15% copper and 72 kg of 60% copper.
What exactly do you need help with
Answer:
1.35kg
Step-by-step explanation:
450g : 6 people
x : 18 people
To get from 6 to 18, multiply by 3 so do the same to the other side
450 × 3 = 1350g
To convert from g to kg divide by 1000
1350 ÷ 1000 = 1.35kg
On the number line, move 4 units to the right. End at -2. The dolphin was 2 feet below sea level.
<h3>What is number line?</h3>
A number lines are the horizontal straight lines in which the integers are placed in equal intervals.
A dolphin was swimming 6 feet below sea level. It then swam up 4 feet.
So, -6+4= -2 feet
As, from the information
On the number line, move 4 units to the right. End at -2. The dolphin was 2 feet below sea level.
This is because the dolphin 6 feet below sea level and swam up 4 feet.
Learn more about this concept here:
brainly.com/question/14379626
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