Answer:
Total length of the first swing=64 m
Step-by-step explanation:
The total length of all four swings can be expressed as;
Total length of all 4 swings=Length of first swing+length of second swing+length of third swing+length of fourth swing
where;
Total length of all 4 swings=175 m
Length of first swing=x
Length of second swing=75% of length of first swing=(75/100)×x=0.75 x
Length of third swing=75% of length of second swing
Length of third swing=(75/100)×0.75 x=0.5625 x
Length of fourth swing=75% of length of third swing
Length of fourth swing=(75/100)×0.5625 x=0.421875 x
replacing;
Total length of all 4 swings
175=x+0.75 x+0.5625 x+0.421875 x
2.734375 x=175
x=175/2.734375
x=64
Total length of the first swing=x=64 m
3/4 and 6/8 are equal and this is right I believe
The answer would be the first one.
One month = 5000
Number of months before the spark plugs need to change :
15000 ÷ 5000 = 3
The sparks can last 3 months before it needs to be changed.
Number of times it need to change in a year = 12 ÷ 3 = 4
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Answer : It needs to be change 4 times a year.
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