What is an equivalent ratio to 1:3

5:15

Step-by-step explanation:

Just times both by a random number, I chose 5

So it would be 1x5=5  and  3x5=15

So take those and boom 5:15

Hope this helps :)

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

15% chance.

step-by-step explanation:

3/10 times, the 5 year old will get a tablet. 5/10 times, the 13 yer old will get a tablet. multiply both fractions to get 15/100 times, both would have a tablet.