How are the triangles similar please help

Anyone know? will mark brainliest if correct!

You are on a cycling trip around europe with friends. you check the weather forecast for the first week. these are the temperatures for the week. sun mon tues wed thurs fri sat 16°c 20°c 24°c 28°c 28°c 23°c 15°c what is the mean temperature forecast for the week?

Nine more than four times a number is the same as one less than twice the number. find the number?