(burn time)/(8 h) = (21 cm)/(14 cm)
burn time = (8 h)*(21/14)
burn time = 12 h
Elio expects the 21 cm candle to burn 12 hours.
-1 is a negative real and rational integer.
2 is a positive real number
is an imaginary or nonreal number.
1 is rational
0 is rational
2 rational counting number
-2 is a negative integer
and do is -1
2 yards is more because 2 yards = 72 inches
Answer: it will take them 2 hours to now 7 lawns
Step-by-step explanation:
It takes Hank 40 minutes (2/3 hours) to mow a lawn. This means that his unit rate of working is 1/40
Penny can mow the same size lawn in 30 minutes (1/2 hour). This means that his unit rate of working is 1/30
If they form a small lawn care company, they will be working together and simultaneously at a faster combined rate. Since their rates are additive.
If they finish one lawn in t hours, working together, then their combined working rate for one lawn is 1/t. Therefore
1/40 + 1/30 = 1/t
1/t = 7/120
t = 120/7 = 17.14
They will now one lawn in 17.14 minutes
For 7 lawns, it will take them 17.14 × 7 = 119.98 minutes. It is approximately 120 minutes.
We will convert from minutes to hour.
60 minutes = 1 hour
120 minutes = 120/60 = 2 hours
Answer:
r + 2
Step-by-step explanation:
To determine which expression evaluates to 5, substitute r = 3 into each expression and evaluate
r - 8 = 3 - 8 = - 5 ≠ 5
r + 2 = 3 + 2 = 5 ← evaluation gives 5
15 - 3 = 12 ≠ 5
3 + 8 = 11 ≠ 5