Is this correct? Am I looking at this correctly or should I use a ph stat formula? Calibri (Body)- A A Aav Aov12AaBbCcDd AaBbCcDd AaBbC AABBCCC AaB AaBBIUV ab x, x A - er A v三。v出、1 Normal1 No Spac. Heading 1Heading 2TitleSubaragranhStulesAutoSaveOnHomework 3 - Saved -O SearchLan PrattFileHomeInsertDrawPage LayoutFormulasDataReviewViewHelpPHStat11- A AE Conditional FormattingCalibriGeneral密InsertPaste$ • % 9Format as TableX Delete vBIU三三州国園Z Cell Styles vEFormat vClipboardFontAlignmentNumberStylesCellsG9frAВCFGH.JKA municipal bond service has three rating categories (A, B, and C). Suppose that of the municipal bonds issued throughoutthe United States in the past year, 70% were rated A, 20% were rated B, and 10% were rated C. Of the municipal bondsrated A, 50% were issued by cities, 40% by suburbs, and 10% by rural areas. Of the municipal bonds rated B, 60% wereissued by cities, 20% by suburbs, and 20% by rural areas. Of the municipal bonds rated C, 90% were issued by cities, 5% bysuburbs, and 5% by rural areas.3 a. If a new municipal bond is to be issued by a city, what is the probability that it will receive an A rating?4 b. What proportion of municipal bonds are issued by cities?5 c. What proportion of municipal bonds are issued by suburbs?50%67%22%7Citiessubarbsrural40%10%8 Rating A9 Rating B10 Rating C111270%50%20%60%20%20%10%90%5%5%200%65%35%4.48nuBasic ProbabilitiesSheet1Sheet2nuBasic Probabilities 4.48Ready WEO QMB-500 Week 3 Homework - Saved -SearchputReferencesMailingsReviewViewHelpA A Aa A三、三、行 EE TAaBbCcDd AaBbCcDd AABBCC AABBCCC A aB AaBbCcD AaBbCcDc1 Normal1 No Spac. Heading 1Heading 2TitleSubtitleSubtle EmParagraphStyles4.48A municipal bond service has three rating categories (A, B, and C). Suppose that of the municipal bonds issued throughout theUnited States in the past year, 70% were rated A, 20% were rated B, and 10% were rated C. Of the municipal bonds rated A, 5were issued by cities, 40% by suburbs, and 10% by rural areas. Of the municipal bonds rated B, 60% were issued by cities, 20 bysuburbs, and 20% by rural areas. Of the municipal bonds rated C, 90% were issued by cities, 5% by suburbs, and 5% by rural areas.a. If a new municipal bond is to be issued by a city, what is the probability that it will receive an A rating?b. What proportion of municipal bonds are issued by cities?c. What proportion of municipal bonds are issued by suburbs?4.53

Question

Is this correct? Am I looking at this correctly or should I use a ph stat formula? Calibri (Body)- A A Aav Aov12AaBbCcDd AaBbCcDd AaBbC AABBCCC AaB AaBBIUV ab x, x A - er A v三。v出、1 Normal1 No Spac. Heading 1Heading 2TitleSubaragranhStulesAutoSaveOnHomework 3 - Saved -O SearchLan PrattFileHomeInsertDrawPage LayoutFormulasDataReviewViewHelpPHStat11- A AE Conditional FormattingCalibriGeneral密InsertPaste$ • % 9Format as TableX Delete vBIU三三州国 園Z Cell Styles vEFormat vClipboardFontAlignmentNumberStylesCellsG9frAВCFGH.JKA municipal bond service has three rating categories (A, B, and C). Suppose that of the municipal bonds issued throughoutthe United States in the past year, 70% were rated A, 20% were rated B, and 10% were rated C. Of the municipal bondsrated A, 50% were issued by cities, 40% by suburbs, and 10% by rural areas. Of the municipal bonds rated B, 60% wereissued by cities, 20% by suburbs, and 20% by rural areas. Of the municipal bonds rated C, 90% were issued by cities, 5% bysuburbs, and 5% by rural areas.3 a. If a new municipal bond is to be issued by a city, what is the probability that it will receive an A rating?4 b. What proportion of municipal bonds are issued by cities?5 c. What proportion of municipal bonds are issued by suburbs?50%67%22%7Citiessubarbsrural40%10%8 Rating A9 Rating B10 Rating C111270%50%20%60%20%20%10%90%5%5%200%65%35%4.48nuBasic ProbabilitiesSheet1Sheet2nuBasic Probabilities 4.48Ready> > >WEO QMB-500 Week 3 Homework - Saved -SearchputReferencesMailingsReviewViewHelpA A Aa A三、三、行 EE TAaBbCcDd AaBbCcDd AABBCC AABBCCC A aB AaBbCcD AaBbCcDc1 Normal1 No Spac. Heading 1Heading 2TitleSubtitleSubtle EmParagraphStyles4.48A municipal bond service has three rating categories (A, B, and C). Suppose that of the municipal bonds issued throughout theUnited States in the past year, 70% were rated A, 20% were rated B, and 10% were rated C. Of the municipal bonds rated A, 5were issued by cities, 40% by suburbs, and 10% by rural areas. Of the municipal bonds rated B, 60% were issued by cities, 20 bysuburbs, and 20% by rural areas. Of the municipal bonds rated C, 90% were issued by cities, 5% by suburbs, and 5% by rural areas.a. If a new municipal bond is to be issued by a city, what is the probability that it will receive an A rating?b. What proportion of municipal bonds are issued by cities?c. What proportion of municipal bonds are issued by suburbs?4.53

Accepted Answer

Given:
A rated 70% of 100=70
B rated 20% of 100=20
C rated 20% of 100=20
From A, 50% for cities…