Answer:40
Step-by-step explanation:This is a variation question
From the statement. Let the mental age be M and the chronological age be C, then
IQ ∝M ∝1/C
⇒ IQ ∝ M/C
Introducing the proportionality constant
IQ = KM/ C
Given : M = 15, C = 30 , 1Q = 20
Substitute the given values into the equation
i.e 120 = K x 15/ 30
120 = k/2
therefore k = 240
substitute k = 240 into the equation, we have
IQ = 240M/C
To find C when IQ is 120 and M is 20, we will substitute into the generated formula
i.e 120 = 240 x 20 / c
120c = 480
C = 480/120
C = 40
Therefore , the chronological age of a person with mental age of 20 and IQ of 120 is 40
3124 = 3000 + 100 + 20 + 4
Ok you answer is d , 6+(-15)
Answer:
Step-by-step explanation:
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Hope this helped!
<h3>~AH1807</h3><h3>Peace!</h3>
Answer:
40
Step-by-step explanation:
Any solution x will mod 23 will also have x+23n as a solution, for some integer n. Since 900/23 = 39 3/23, we know there are 39 or 40 three-digit integers of this form.
As it happens, 100 is the smallest 3-digit solution. So, there are 40 three-digit numbers that are of the form 100 +23n, hence 40 solutions to the equation.
_____
The equation reduces, mod 23, to ...
10x = 11
Its solutions are x = 23n +8.
