1. Simplify the NumbersFirst, we isolate the last two digits of each number in the product, as the hundreds digit (the "2" in 201 or 246) does not affect the last two digits of the result. The product becomes:
(01⋅02⋅03⋅04⋅46⋅47⋅48⋅49)^2
2. Multiply in Small GroupsWe can calculate the last two digits by multiplying these in pairs and keeping only the last two digits at each step:
Group 1: 1⋅2⋅3⋅4=24
Group 2: 46⋅47=2162→ Last two digits are 62
Group 3: 48⋅49=2352→ Last two digits are 52
3. Combine the GroupsNow, we multiply these intermediate results together:
Step A: 24⋅62 = 1488→ Last two digits are 88
Step B: Multiply that result by the remaining group (88⋅52):
88⋅50 = 4400 (ends in 00)
88⋅2 = 176 (ends in 76)
4400+176 = 4576→ Last two digits are 76
The value inside the parentheses ends in 76.
4. Square the Final ResultFinally, we square the result to account for the exponent outside the parentheses:
76⋅76 = 5776
The last two digits are 76.
Why does 76 appear again? In mathematics,
76 is a special number called an automorphic number. When you multiply any number ending in 76 by another number ending in 76, the result will always end in 76.
Correct Answer: E. 76