Answer:
The answer is 30 months
Step-by-step explanation:
900 divided by 12 months = 75/month
2250 divided by 75 each month = 30 months
12% as a fraction is 12/100 but it’s simplest form is 3/25
U first start of with writing the numbers from small to greatest so it will be 45,53,53,54,60,62,63,67,68 after that your min will be your smallest, 45 and your Max is 68 than for you mid you start off at both ends with your finger ( if needed) to get your middle which in this case, it’s 60. Now for your Q1 u do the exact same thing for mid but instead of you start from 45 to 60 which gets u to 53 as ur Q1. Finally for your Q3 you you starting off at 60 and ending at 68 and doing the same thing again ur Q3 will be 63.
Let Mary Sue have m necklaces and Betty have b necklaces.
And they have 603 necklaces altogether, that is
m + b =603
And Mary Sue has 115 more necklaces than Betty, that is
m=b +115
Substituting this value in first equation we will get
b+115+b=603
Subtracting 115
2b= 488
b= 244
So Betty have 244 necklaces .