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Crawling Crayfish!
Big Claw, the crayfish, challenged Flicker to a 60 em race. Since Big Claw is much
larger, he offered to give Flicker a 10 cm head start Flicker agreed and the race
began. After 5 seconds, Big Claw had crawled 6 cm and Flicker had crawled 4 cm.
If they continue at this rate, who do you predict will win the race? justify your
prediction
How many seconds have elapsed when Big Claw and Flicker are tied?

Respuesta :

Answer: Crayfish, 25 s

Step-by-step explanation:

Given

The length of race is 60 cm

Flicker gets a 10 cm head-start

Cray fish covers 6 cm in 5 s i.e. its speed is

[tex]\Rightarrow \dfrac{6}{5}=1.2\ cm/s[/tex]

Flicker covers 4 cm in 5 s, its speed is

[tex]\Rightarrow \dfrac{4}{5}=0.8\ cm/s[/tex]

Time taken by Cray fish to cover the race is

[tex]\Rightarrow t_1=\dfrac{60}{1.2}\\\\\Rightarrow t_1=50\ s[/tex]

Time taken by flicker to cover race with 10 cm head start

[tex]\Rightarrow t_2=\dfrac{60-10}{0.8}\\\\\Rightarrow t_2=62.5\ s[/tex]

Time taken by crayfish is less. Hence, crayfish wins the race

When they both covers the same distance, they tied momentarily i.e.

[tex]\Rightarrow 1.2t=10+0.8t\\\Rightarrow 0.4t=10\\\\\Rightarrow t=\dfrac{10}{0.4}\\\\\Rightarrow t=25\ s[/tex]

After 25 s, they tied the race.