Answer:
1 560
Step-by-step explanation:
If no digit (from the digits 3, 4, 5, 6, 7, 8) can be used more than once :
we can form 6P5 = 720 (five-digit numbers) and they are all > 7000
we can form 6P6 = 720 (six-digit numbers) and they are all > 7000
if our number has four digits ,then the digit in the ten-thousands place of it must be 7 or 8 :
In this case :
we can form 5P3=60 number where the digit in the ten-thousands place of it is 7.
and we can form 5P3=60 number where the digit in the ten-thousands place of it is 8.
Final answer :
We can form 720+720+60+60 = 1 560 number greater than 7000
