Let x = the total number of pennies her piggy bank can hold.
Then 2/3x = the number of pennies she started with
Then 2/3x - 80 = the number of pennies she has left after taking out 80 pennies.
Then 1/2x = the number of pennies she has left after taking out 80 pennies.
Build the equation.
2/3x - 80 = 1/2x
Subtract 1/2x from each side of the equation.
(2/3x - 80) - 1/2x = 1/2x - 1/2x
1/6x - 80 = 0
Add 80 to both sides of the equation.
(1/6x - 80) + 80 = 0 + 80
1/6x = 80
Divide both sides by 1/6.
(1/6x) / 1/6 = 80 / 1/6
x = 480
So, Linda's piggy bank can hold 480 pennies!
#22. We are given that y = 1/4. So, we want to plug this value into the expression 15/y:
15/(1/4)
When you divide by a fraction, you should follow the rule “flip the guy and multiply”. Basically, 15/(1/4) = 15 * 4 = 60.
The answer for #22 is (D).
#23. We can use a proportion:
(The shaded area)/(entire circle area) = (360 - 60)/360
But, we don’t have to find the areas of the region and circle; we can just solve the fraction:
(360 - 60)/360 = 300/360 = 30/36 = 5/6
The answer for #23 is (A).
Scalene I believe. Hope this helps!
the more years the money stays invested, the more interest it earns, so clearly, if the compounding cycle is the same for both options, and the rate of 7% is the same as well for both, then the one with more years will give more interest..
so depends on what "best" means in this context, but if it's more interest earned, 3 years gives more interest than 2 years of course.
