1x15=15 3x5=15 so 1 times 15 3x5=15
Answer:
an intervening time
Step-by-step explanation:
Answer:
multiply by 12: r = 18
Step-by-step explanation:
Use the multiplication property of equality. It tells you that multiplying both sides of an equation by the same value does not change the values of any of the variables. Here we can multiply by 12 and we get ...
r(12/12) = 1.5(12)
Now, the properties of the identity element for multiplication come into play. When we multiply r by 12/12=1, we do not change the value of r, so we can simplify this to ...
r = 18
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We chose to multiply by 12 precisely because 12/12 = 1, and the result on the left side of the equation is r.
Answer:
Step-by-step explanation:
Let the rate of boat in still water be b and the speed of the current be c
- Speed downstream = b + c
- Speed upstream = b - c
<u>We got equations for time:</u>
- 108/(b - c) = 3 ⇒ b - c = 36
- 108/(b + c) = 2 ⇒ b + c = 54
<u>Add up the equations:</u>
- b - c + b + c = 36 + 54
- 2b = 90
- b = 45 km/h
<u>Then finding the values of c</u>
