Write down a formola in which the speed of v is expressed in the passable way of s and time of t as the value private will change if to increase a divider by 3 times and not to change a dividend check justice of this rule for a dividend of 120 and two dividers 20 and 60

V=S/t... 20/120=1/6...60/120=1/2. Let's increase by 3 times 20 and 60, we will receive 60/120=1/2.180/120=3/2 i.e. private increased by 3 times too. Further 180/2=90. Let's increase time (2) by 3 times, we will receive 180/6=30t. e. private decreased by 3 times. It is necessary to increase speed by 4 times. At first we will find speed on the formula stated above V=240/8=30. Let's increase speed 30*4=120. Also we will find time on formula t=S/V, t=240/120=2. Time decreased by 4 times. t1=8 t2=2.
Answer add