What all is equivalent to 75:50

Not sure what you mean by "all". If you literally meant all the ratios that are equivalent to 75:50, the answer would be basically infinite. Maybe you mean in simplest terms, which is most commonly answered. In that case, the answer is 3:2

i dont understand the question? ?

step-by-step explanation:

the 8 in 8,420 is in the thousands place so it's value is 8 thousand.

the 8 in 6,870 is in the hundreds place so it's value is 8 hundred.

divide 8000 by 800 to find the answer:

8000 / 800 = 10

the 8 in 8,420 is 10 times greater than the 8 in 6,870