Answer:
Mean age = 1271.27
Step-by-step explanation:
No of children = 77
The age at which children first began to combine words = 16.51 months
Mean age = No of children × age at which children first began to combine words
= 77 × 16.51
= 1271.27
Mean age = 1271.27
Rounding the answer is 100.
Answer:
(1,2)
y=2
x=1
Step-by-step explanation:
x+y=3
3x+5y=13
solve the equation
x=3-y
3x+5y=13
substitute the value of x into an equation
3(3-y)+5y=13
distribute
9-3y+5y=13
add -3y to 5y
9+2y=13
subtract 9 from both sides
2y=4
divide both sides by 2
y=2
substitute the value of y into an equation
x=3-2
subtract 3 to 2
x=1
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(1,2)
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She has 45% of the original amount left
<h3>Ratio and proportions</h3>
Fractions are written as a ratio of two integers
Given the following
Initial amount. = ∈4000
Amount given to her sister = 1/4 * 4000 = 1000
Amount given to her brother = 40% of 3000 = 1200
Amount left = 4000 - (1000+1200)
Amount left = ∈1800
Determine the percentage left
x * 4000 = 1800
x = 1800/4000
x = 0.45
x = 45%
Hence she has 45% of the original amount left
Learn more proportion here: brainly.com/question/19994681
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