Question

Find the number of those 4-digit numbers whose digits are non-increasing.

a) 715
b) 870
c) 330
d) 475

Answer 1

The student's question relates to finding 4-digit numbers with non-increasing digits; only 870 meets this criterion among the options provided.

Step-by-step explanation:

The student is asking to find the number of those 4-digit numbers whose digits are non-increasing. In mathematical terms, a non-increasing sequence is one in which each digit is less than or equal to the preceding digit. to answer this, we'll evaluate each option provided:

• a) 715 - This is not a 4-digit number.
• b) 870 - The digits are non-increasing (8 ≥ 7 ≥ 0).
• c) 330 - This is not a 4-digit number.
• d) 475 - The digits are not non-increasing (since 7 < 5).

Therefore, from the options given, the only 4-digit number with non-increasing digits is 870.