The number is 300. 50% of 300 is 150 so
75% of 300 is 225!
Equation 1: x + y = 40 ; therefore y = 40 - x
Equation 2: 25x + 15y = 900
Find x first:
25x + 15 (40 - x) = 900
25x + 600 - 15x = 900
10x = 900 - 600
x = 300÷10
x = 30 hours Chris needs to spend for tutoring job
y = 40 - 30
y = 10 hours Chris needs to spend for referencing job
First off, you have to convert 8 minutes into seconds.
A minute is <em>60 seconds</em>, so multiply 60 by 8.
60×8=480
Now, change 10⁹ into a standard number. Since the number is 10 that is to have an exponent, the exponent, in this case 9, indicates how many zeros are in the standard number.
10⁹=1,000,000,000
So, multiply 480 by 1,000,000,000.
480×1,000,000,000=480,000,000,000
So, the answer is 480,000,000,000.
