గరిష్ఠ దశాంశ స్థానాలు: 6; దగ్గరి విలువ; సమదూరంలో సున్నాకు దూరంగా
Sum of weights
100%
Sum of value × weight
8,290
Number of values
3
Unweighted average
85
The weighted average is 82.9: the products add up to 8,290 and the weights to 100. The unweighted average is 85; Final exam, with the largest weight (50% of the total), pulls the result down toward 78.
What each value adds to the weighted average
Share of the total weight
Homework20%Midterm30%Final exam50%
Each value's share వరుసలు: 3
Item
విలువ
Weight
Share of weight
Value × weight
Contribution
Homework
92
20
20 %
1,840
18.4
Midterm
85
30
30 %
2,550
25.5
Final exam
78
50
50 %
3,900
39
గణన చేసే విధానం S
Multiply each value by its weight
92×2085×3078×50=1,840=2,550=3,900
Add the products and the weights
∑wx=1,840+2,550+3,900=8,290∑w=20+30+50=100
Divide
xˉw=∑w∑wx=1008,290=82.9
Compare with the unweighted average
xˉ=n∑x=3255=85
Weighting moves the average down by 2.1.
భారిత సగటు కాలిక్యులేటర్ గురించి
A weighted average multiplies each value by its weight, adds the products and divides by the sum of the weights: Σwx ÷ Σw. Values with larger weights pull the result toward themselves, and with equal weights it is the ordinary mean.
Course grades are the usual case. With homework at 92 counting 20%, the midterm at 85 counting 30% and the final at 78 counting 50%, the products add up to 8,290 and the weights to 100, so the weighted average is 82.9, while the plain average of the three scores is 85. Weights can be credits for a GPA, share counts for an average purchase price, or any relative importance.
Weights only need to be in proportion: 20%, 30% and 50% give the same answer as 2, 3 and 5. They must not be negative, and at least one must be above zero. A label before the numbers on a line, such as “Final exam”, is carried into the table.
పరిష్కరించిన ఉదాహరణలు
Course grade (default)
Values and weights
Homework 92 20%
Midterm 85 30%
Final exam 78 50%
భారిత సగటు
82.9
Sum of weights
100 %
Sum of value × weight
8,290
Number of values
3
Unweighted average
85
తనిఖీ చేసిన మూలం: Hand calculation: (92 × 20 + 85 × 30 + 78 × 50) / 100 = 8290 / 100 = 82.9
GPA by credit hours (Inch Calculator example)
Values and weights
3.0 4
4.0 3
3.7 4
3.3 3
భారిత సగటు
3.48
Sum of weights
14
Sum of value × weight
48.7
తనిఖీ చేసిన మూలం: Inch Calculator weighted average page: (3.0×4 + 4.0×3 + 3.7×4 + 3.3×3) / 14 = 48.7 / 14, GPA 3.48
GPA with four classes (Omni Calculator example)
Values and weights
A 4 4
B 3 4
A 4 3
C+ 2.3 2
భారిత సగటు
3.430769
Sum of weights
13
Sum of value × weight
44.6
Unweighted average
3.325
తనిఖీ చేసిన మూలం: Omni Calculator weighted average page: (4·4 + 3·4 + 4·3 + 2.3·2) / 13 = 3.43; Python Fraction(446, 130) = 3.4307692…
Average share price
Values and weights
100 10
110 20
భారిత సగటు
106.666667
Sum of value × weight
3,200
Sum of weights
30
Unweighted average
105
తనిఖీ చేసిన మూలం: Hand calculation: (100 × 10 + 110 × 20) / 30 = 3200 / 30 = 106.67
ప్రశ్నలు
How do you calculate a weighted average?
Multiply each value by its weight, add the products, and divide by the total weight. For scores of 92, 85 and 78 weighted 20%, 30% and 50%: 92 × 20 + 85 × 30 + 78 × 50 = 8,290, and 8,290 ÷ 100 = 82.9. In a spreadsheet the same formula is =SUMPRODUCT(values, weights)/SUM(weights).
Do the weights have to add up to 100%?
No. Dividing by the sum of the weights rescales them automatically, so weights of 2, 3 and 5 give the same result as 20%, 30% and 50%. If percentage weights add up to 90% because a grade item is still missing, the result is the average of the work done so far, with each item's weight divided by 0.9.
How do you calculate a weighted GPA?
Use the grade points as values and the credit hours as weights. For a B (3.0) in a 4-credit class, an A (4.0) in 3 credits, an A− (3.7) in 4 credits and a B+ (3.3) in 3 credits, the quality points are 12 + 12 + 14.8 + 9.9 = 48.7 over 14 credits, a GPA of 3.48. The GPA calculator converts letter grades for you.
What is the difference between a weighted average and a simple average?
A simple average gives every value the same weight, 1/n. A weighted average lets some values count more. For the default grades the simple average is (92 + 85 + 78) ÷ 3 = 85, but the final exam, worth half the grade, pulls the weighted average down to 82.9. The two agree only when all weights are equal.
How do you find the average price of shares bought at different prices?
Weight each price by the number of shares bought at it. Buying 10 shares at $100 and 20 at $110 costs $1,000 + $2,200 = $3,200 for 30 shares, an average of $106.67 per share, not the $105 you get by averaging the two prices. This weighted average is the cost basis per share used to work out a gain or loss.
“భారిత సగటు కాలిక్యులేటర్” ఎంత కచ్చితమైనది?
కచ్చితత్వం మీ ఇన్పుట్లు, పద్ధతిలోని ఊహలపై ఆధారపడి ఉంటుంది. దశాంశ గణన 50 సార్థక అంకెలను ఉపయోగిస్తుంది. అంచనాలు, సంఖ్యా పద్ధతులు, మూల డేటా తక్కువ కచ్చితత్వంతో ఉండవచ్చు; ప్రదర్శనలో విలువలను రౌండ్ చేయడం ఈ పరిమితులను తొలగించదు. స్వతంత్ర మూలాల పరిష్కారాలతో తనిఖీ చేసిన ఉదాహరణలు: 7. ఉదాహరణకు, “Course grade (default)”ను Hand calculation: (92 × 20 + 85 × 30 + 78 × 50) / 100 = 8290 / 100 = 82.9తో తనిఖీ చేశారు.
ఈ కాలిక్యులేటర్లో స్వతంత్ర ఆధారాల నుంచి సమాధానాలు పొందిన 7 సాధించిన ఉదాహరణలు ఉన్నాయి. ఇవి పరీక్షల సమూహంలో అమలవుతాయి; మీరు ఇక్కడ కూడా వాటిని అమలు చేయవచ్చు.