Let's say x = 15% copper and y = 75% copper
We need 120 kg of a 51% copper alloy.
A) x + y = 120
B) .15x + .75y = 61.2 (which is 120*.51%)
Multiplying A by -.15
A) -.15x -.15y = -18 Then add this to B
.60y = 43.2
y = 72
x = 48
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http://www.1728.org/mixture.htm
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Double Check
48 kilograms of .15% copper = 7.2 kg copper
72 kilograms of .75% copper = 54 kg kg copper
So we have 61.2 kg of copper in 120 kg
61.2 / 120 = .51 = 51%
50 yd= 1,800 in
48 ft= 16 yd
Answer:
Align the numbers on the decimal point. Place a zero in the hundredths place of 81.3. Subtract from right to left, regrouping as necessary.
Step-by-step explanation:
The angles and side lengths for both triangles are;
3) A = 36°; B = 54°; C = 90°; a = 7; b = 9.63; c = 4.11
4) A = 64°; B = 26°; C = 90°; a = 1.798; b = 0.88; c = 2
<h3>How to solve Pythagoras theorem?</h3>
3) From the diagram, we are already given;
B = 54°
C = 90°
a = 7
We know that sum of angles in a triangle is 180° and so;
A = 180 - (90 + 54)
A = 36°
By trigonometric ratios;
b/7 = tan 54
b = 7 * tan 54
b = 7 * 1.376
b = 9.63
7/c = cos 54
c = 7 * cos 54
c = 4.11
4) From the diagram, we are already given;
B = 26°
C = 90°
c = 2
We know that sum of angles in a triangle is 180° and so;
A = 180 - (90 + 26)
A = 64°
By trigonometric ratios;
b/2 = sin 26
b = 2 * sin 26
b = 2 * 0.4384
b = 0.88
a/2 = cos 26
a = 2 * cos 26
a = 1.798
Read more about Pythagoras Theorem at; brainly.com/question/654982
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