Question

Need help please with explanations ❤️

Answer 1

Answer:

It will take Jack about 7.1 hours alone

Step-by-step explanation:

You are given the equation

t/a + t/b = 1

where t is the time working together, a is the time Jill spends working alone, b is the time Jack spends working alone

Substituting these numbers in

3.2/5.8 + 3.2 /b = 1

Multiply both side by 5.8b to clear the fractions

5.8 b * (3.2/5.8 + 3.2 /b )= 1*5.8b

Distribute

3.2b + 5.8*3.2 = 5.8b

Subtract 3.2b on each side

3.2b -3.2b+ 5.8*3.2 = 5.8b-3.2b

5.8*3.2 = 2.6b

18.56 = 2.6b

Divide by 2.6 on each side

18.56 /2.6 = 2.6 b/2.6

7.138 = b

It will take Jack about 7.1 hours alone