Alissa emptied her piggy bank for disney world. She had $7.70. if she had 10 pennies, twice as many times as quarters, and 1/2 as many nickels as quarters, how many quarters did she have?

She has 20 quarters.

Step-by-step explanation:

Alissa emptied her piggy bank for Disney world. She had $7.70.

If she had 10 pennies and twice as many times as quarters, then we can write the equation as

Q = 2P {Where, Q represents the number of quarters and P for pennies}

⇒ Q = 10 × 2

⇒ Q = 20

So, she has 20 quarters.

Therefore, she has 20 quarters. (Answer)

i got 10.28 but that rounds up to 10.3

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places