8 tens and 4 one
(3*10)+(9*1)=39
8 tens.
500+10+6 = 516
9 rounds up to 10. You can't put ten tenths in one place, you need to regroup and increase the ones by one.
One ten is equal to ten ones
78 can be regrouped into 6 tens and 18 ones.
yes
(3*10)+(9*1)=39
With addition, you need to regroup in the event that there are more than 10 ones or 10 tens. In a subtraction, you must regroup whenever there are insufficient ones or tens to subtract.
6+6 7+7 10+8 6+4
8 tens.
500+10+6 = 516
9 rounds up to 10. You can't put ten tenths in one place, you need to regroup and increase the ones by one.
10+6
Ten of them because 10*1 = 10
One ten is equal to ten ones
10 ones equall 1 ten