Sample space: H1, H2, H3, H4, T1, T2, T3, T4
All outcomes if the card is three: H3, T3
I was unclear about the last two parts of the question.
Let q and n represent the number of quarters and nickels respectively.
q=3n and .05n+.25q=1.6 These are the conditions in mathematical terms.
To solve, use the value of q from the first equation in the second equation to get:
.05n+.25(3n)=1.6 carry out indicated multiplication on left side
.05n+.75n=1.6 combine like terms on left side
.8n=1.6 divide both sides by .8
n=2, since q=3n
q=6
So Peggy had 2 nickels and 6 quarters.
5(4+y) is the correct answer, you would be adding 4 and y then multiplying the sum by 5
X would have to equal 2 because when you multiply that by 7 you get 14 then add 3 and you get 17