Using front-end estimation, find a reasonable estimate of:

21,000

Step-by-step explanation:

front end estimation requires you to take the front / first digit of each number in this expression and round.

if you don't know how to round, basically you take the next digit after the first one, (in 719 you take the 1) and determine if that's below or above 5. If below, then keep the original first number. If above, add one more to the first digit. If the number is five itself, it is most common to round up (so add one).

like 425 would round to just 400; and 676 would round to 700.

multiply  700 and 30

youd get 21000

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.