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Mount Mansalu is the eighth highest mountain in the world, with its peak 8,156 meters above sea level.
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The shores of the Dead Sea, Earth’s lowest land elevation, are 430.5 meters below sea level.
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What is the difference between these two elevations?
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We are told that the mountain has a peak of 8,156 meters above sea level.
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This can be represented by the number positive 8,156.
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We’re also told that the shores of the Dead Sea are 430.5 meters below sea level.
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This can be represented by the number negative 430.5.
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To calculate the difference between the two elevations, we could use one of two methods.
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Firstly, as difference means subtract, we could subtract negative 430.5 from 8,156.
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Subtracting a negative number is the same as adding the absolute value of that number.
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We have 8,156 plus 430.5.
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This gives us a total of 8,586.5.
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The difference between the two elevations is 8,586.5 meters.
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Our alternative method would be to add the absolute value of both numbers.
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The absolute value or modulus of a number is denoted by two vertical parallel lines, as shown.
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We have the absolute value of 8,156 plus the absolute value of negative 430.5.
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The absolute value of any number is the distance between the number and zero.
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As the absolute value of any negative number is positive, we’re left with 8,156 plus 430.5 once again.
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This gives us the same answer of 8,586.5 meters.