Question

Rohan ,Amber,and Sahara were discussing the following problem .A submersible dives from the surface at 15m/min for 6 min and then at 25m/min for 20 min. What is the depth of the submersible after the dive?They worked together to write the following expression to solve the problem.
6×(-15) +20×(-25)Then they evaluated the expression independently.
Rohan evaluated the expression as +1750.
Amber evaluated the expression as -590.
Sahara evaluated the expression as -750.Explain how the expression represents the problem.
Which student evaluated the expression correctly?
How do you know?What errors did the other two students make?What is the depth of the submersible after the dive

Answer 1

Solution :-

since , depth below below sea level (or from the surface) is shown by taking negative numbers.

→ Speed for first 6 minutes = 15 m/ min .

So,

→ Distance covered = Depth = S * T = 15 * 6 = 90 m = (-90m)

and,

→ Speed for next 20 minutes = 25 m/ min .

So,

→ Distance covered = Depth = S * T = 25 * 20 = 500 m = (-500m)

then,

→ The depth of the submersible after the dive = (-90m) + (-500m) = (-590m) = 590 m from the surface .

therefore,

→ The expression represents the problem = {6 * (-15) + 20 * (-25)} m

hence, Amber evaluated the expression correctly .

Learn more :-

solution of x minus Y is equal to 1 and 2 X + Y is equal to 8 by cross multiplication method

https://brainly.in/question/18828734