By 20 because 20 x 5 is 100
The answer is X = 12.
This is how to get that answer: the formula for the intersecting secant and tangent outside the circle is a^2 = b(b+c) If you use the numbers in the pic you will get x^2 = 9(9+7) so the number after the equal sign will be 144, so x^2 = 144. To undo the square youre gonna use the square root on both sides, so you have X = 12.
Ten cakes costs $2.19 (pounds, but I don't have a pounds symbol on my computer) because if you divide $2.10 by seven you get $0.3, and if you add 3×0.3 (because we have seven, and we need to add three more to get ten) we get $0.9.
0.9+2.10=2.19
Answer: Mary
Step-by-step explanation: 2:3 x 2 = 4:6