Respuesta :
Answer:
The last two digits of 6²⁰²⁰ + 7²⁰²⁰ is 7, 7
Step-by-step explanation:
The given question is to find the value of the sum of two numbers 6²⁰²⁰ + 7²⁰²⁰, where, 6²⁰²⁰ + 7²⁰²⁰ ≠ 13²⁰²⁰
We have;
The last two digits of the powers of 6 are;
6¹ = 6, last two digits = 06
6² = 36, last two digits = 36
6³ = 216, last two digits = 16
6⁴ = 1,296, last two digits = 96
6⁵ = 7,776, last two digits = 76
6⁶ = 46,456, last two digits = 56
6⁷ = 279,936, last two digits = 36
6⁸ = 1,679,616, last two digits = 16
6⁹ = 10,077,696, last two digits = 96
6¹⁰ = 60,466,176, last two digits = 76
6¹¹ = 362,767,056, last two digits = 56
Therefore, the last two digits repeat itself every 5 times
For 6²⁰²⁰, the last two digits will be for the 2020/5 = 404 complete times, which will be 76
The last two digits of the powers of 7 are;
7¹ = 7, last two digits = 07
7² = 49, last two digits = 49
7³ = 343, last two digits = 43
7⁴ = 2,401, last two digits = 01
7⁵ = 16,807, last two digits = 07
7⁶ = 117,649, last two digits = 49
7⁷ = 823,543, last two digits = 43
7⁸ = 5,764,801, last two digits = 01
Therefore, the last two digits repeat itself every 4 times
For 7²⁰²⁰, the last two digits will be for the 2020/4 = 505 complete times, which will be 01
Therefore, the last two digits of 6²⁰²⁰ + 7²⁰²⁰ is 76 + 01 = 77, which is 7, 7
