72/126 - 49/126 = 23/126
53
53/8
No 58 x 5 = 290 but 58 - 5 = 53 so change times to minus
Iodine has 53 protons. Iodine 126 has 126 - 53 = 74 neutrons. So iodine 126 is called iodine 16 because it has 53 protons and 74 neutrons. There are other types of iodine, called neuclides of iodine, which have different numbers of neutrons. All of them have 53 protons. So iodine 141 has 53 protons and 141 - 53 = 88 neutrons.
- 20 - 38 - (-53) = -58 + 53 = -5
126+126=252
127 - 53 = 74
(-53) - 17 = -70
71 - 53 = 18
The answer is 8. You know that is just 61-53=8.
53 minus 20% of 53 is 42.4