This means that it sweeps out half of the circle so that the chord is actually going across the whole diameter of the circle. So if the chord is going across the diameter and has a length of 15 inches, then the radius of the circle should be 7.5 inches. read more at: https://www.ck12.org/trigonometry/Length-of-a-Chord/lesson/Length-of-a-Chord-TRIG/
Consider, pls, this option:
1) let start price is 'x' and the 1-t increasing is 'y';
2) after the 1-t increasing new1_price is x(y+1);
3) after the 2-d increasing new2_price is 1.25x(y+1);
4) from another side, new2_price is '2x';
5) according to five items it is possible to make up an equation: 1.25x(y+1)=2x;
1.25(y+1)=2, y=8/5 -1=3/5=0.6.
0.6 means 60%.
Answer: 60%.
(x+40):12=88-78
(x+40):12=10
x+40=10*12
x+40=120
x=120-40
x=80
