He messed up step 2 he added instead of multiplying
Answer:
Step-by-step explanation 10 + 2.50d = 850
David starts with $10 and each day he earns $2.50. The d represents a variable and can be any number.
To find d you must solve the equation.
10 + 2.50d = 850
2.50d = 840 (subtract 10 from 850)
d = 336 (divide 840 by 2.50)
It will take David 336 days to save $850.
Answer:
1.5 hours to 525 km
Speed in km/h=

Step-by-step explanation:
XD
You can count the spirals because they are coloured.
The left handed spirals are in red and you can count 13.
The rifht hanged spirals are in yellow and you can count 21.
Fibonacci sequence is: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... From 2 the next number is the sum of the two previous numbers:
2 = 1 + 1
3 = 2 + 1
5 = 3 + 2
8 = 5 + 3
13 = 8 + 5
21 = 13 + 8.
Fibonacci numbers are found in many structures in nature.
We have just found that these cacti enclose Fibonacci numbers 13 and 21.
Answer: 13 and 21