The radius of the Outer circle (with r₂) is 6 and the radius of the inner circle (with r₁) is 2. When objects are similar, they have a proportional relationship. If we take the outer circle and squeeze by one third, we get a radius of 6 x 1/3 = 2. On the other hand, if we start with the inner circle and stretch it by 3, we get a radius of 2 x 3 = 6.
Thus, to make r₂ similar, we use a scale factor of 1/3. The third choice is best.
The penny can land two ways.
The nickel can land two ways.
The dime can land two ways.
The quarter can land two ways.
The total number of ways that all of them can land is (2x2x2x2)= 16 possibilities.
Only ONE result shows no heads . . .
TAIL-TAIL- TAIL-TAIL.
All of the other 15 possibilities include at least one HEAD. So the probability is 15/16 = 93.25% .
8 and 7 are both a factor of 56.
