Answer:
10 calories were burned for each minute of jogging and 10 calories were burned for each minute of cycling.
Step-by-step explanation:
Let be "j" the amount of calories Shelly burned for each minute of jogging and "c" the amount of calories Shelly burned for each minute of cycling.
Set up a system of equations:
[tex]\left \{ {{10j+20c=300} \atop {20j+10c=300}} \right.[/tex]
You can apply the Elimination method: multiply the first equation by -2, then add the equations and solve for "c":
[tex]\left \{ {{-20j-40c=-600} \atop {20j+10c=300}} \right.\\...............................\\-30c-300\\\\c=10[/tex]
Now, substitute the value of "c" into any original equation and solve for "j":
[tex]10j+20(10)=300\\\\10j=300-200\\\\10j=100\\\\j=10[/tex]
