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3 years ago

Solving simultaneous equations by algebraic methods 3a+4x=29 2a-3x=-9

1 answer:

4 0

3a+4x=29 (1st)
2a-3x=-9 (2nd)

multiply (1st) by 3 and (2nd) by 4

9a + 12x = 87 (1st)
8a - 12x = -36 (2nd)
---------------------add
17a = 51
a = 3

2a-3x=-9
2(3)-3x=-9
6 - 3x = -9
-3x = -15
x = 5

answer
x = 5 and a = 3

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2 years ago

The average speed of greyhound dogs is about 18.4 meters per second. A particular greyhound breeder claims that her dogs are fas

irinina [24]

Answer:

The calculated value Z = 1.183 < 1.96 at 0.05 level of significance

Null hypothesis is accepted

A particular greyhound breeder claims that her dogs are faster than the average greyhound

Step-by-step explanation:

Step(i):-

Given the average speed of greyhound dogs is about 18.4 meters per second.

Size of the sample 'n' = 35

mean of the sample x⁻ = 18.7

Population standard deviation = 1.5m/s

level of significance (∝) = 0.05

Step(ii):-

Null hypothesis : H₀ : μ = 18.4

Alternative hypothesis H₁ : μ ≠ 18.4

Test statistic

$Z = \frac{x^{-} - mean}{\frac{S.D}{\sqrt{n} } }$

$Z = \frac{18.7-18.4}{\frac{1.5}{\sqrt{35} } }$

Z = 1.183

Conclusion:-

The calculated value Z = 1.183 < 1.96 at 0.05 level of significance

Null hypothesis is accepted

A particular greyhound breeder claims that her dogs are faster than the average greyhound

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2 years ago