Answer: 4 science questions and 5 math questions
<u>Step-by-step explanation:</u>
To guess, you know that no matter how many 10 point questions you answer, the result will end in a zero. The number given is 85 so find a number you can multiply by 9 that ends in a 5. Answer: 9(5) = 45
The remaining points (40) are divisible by 10.
40 ÷ 10 = 4
Check: 5 (9-point questions) + 4 (10-point questions) = 9 total questions
45 points + 40 points = 85 points
Note that this problem can be solved mathematically by setting up a system of equations:
Points: 9x + 10y = 85
Quantity: x + y = 9
Answer:25
Step-by-step explanation:
30-(18-12)
30-5=25
Let the two numbers be x and y with x being the greater number.
Given,
x = 7 + y
Also given,
x + y = 39
Substituting the value of x from above,
7 + y + y = 39
7 + 2y = 39
2y = 39 - 7
2y = 32
y =
y = 16
x = 7 + y
x = 7 + 16
x = 23
Hence, the two numbers are 23 and 16.
Answer:
64.13
Step-by-step explanation:
7.13 would be the monthly interest, so mulitiplying that by 9 should give u a 64.13