There are some green counters and some red counters in a bag. At the start, 7 of the counters are green, the rest are red.
Jacinta takes at random a counter from the bag. She does not put the counter back in the bag.
Jacinta then takes at random another counter from the bag.
The probability that the first counter Jacinta takes is red and the second is green is 21/80
Work out the number of red counters in the bag at the start.

What expression is equivalent to 42x-56y

A25- foot ladder leans against a building and reaches a point of 23.5 feet above the ground .find the angle that the ladder makes with the building

Hey everyone! this question is a challenge question. for 50 points if you wish. all you have to do is answer the correct it has to be correct, in under 50 seconds, and i will make you the ! you want to accept this challenge. i already know! i mean, it's 50 free points! here is the question: 11x2= answer this correct, you get two prizes. don't forget. you only have 50 seconds or it wont happen. get it correct in under 50 seconds! that's not bad. so stop reading this long thing and !