A piggy bank contains six times as many quarters as dimes. If the total amount of money is $28.80, how many quarters and dimes are in the piggy bank?

9514 1404 393

Step-by-step explanation:

A group of 6 quarters and 1 dime has a value of $1.60. Then there are ...

  $28.80/$1.60 = 18

groups like that in the piggy bank.

The number of quarters is 18×6 = 108.

The number of dimes is 18×1 = 18.

There are 108 quarters and 18 dimes in the piggy bank.

i dont know

step-by-step explanation:

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