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# This is my math question: mildred has seven grades on her report card. the overall average of these seven grades is 77%. after looking more closely at her report card, mildred discovered that her english grade was incorrectly recorded as 18% instead of her actual grade of 81%. determine mildred’s correct report card average. i want to know the steps to complete this i do not want the answer just the steps to complete this

• Réponse publiée par: girly61
The correct report card average for 7 subjects is 85%.

Step-by-step explanation:

If average is 77% and the incorrectly recorded English subject is 18:

Total subjects: 7

Average: 77%

English subject: 18%

Average grade in other 6 subjects: x

Total grades in other 6 subjects: 6x

Find x, the average grade in other 6 subjects:

(6x + 18)/7 = 77

6x + 18 = 77(7)

6x = 539 - 18

6x/6 = 521/6

x = 86.83  average grade of 6 other subjects

Find the new average y of the 7 subjects grades if English is corrected at 81%.

(6x + 81)/7 = y

Substitute x = 86.33

y = [6(86.83) + 81]/7

y = [520.98 + 81]/7

y = [601.98]/7

y = 85.99 or 85%  correct average

The correct report card average for 7 subjects is 85%.

• Réponse publiée par: 09389706948
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