Two numbers are in the ratio 7:5. If they differ by 18, find the numbers.( show the steps)
Answers
Step-by-step explanation:
Setting up two equations to solve for 2 unknowns. Let A = one number and B=the other number: First equation:
A/B=7/5 Multiply by B
A = 7B/5 Multiply by 5
5A = 7B or
5A - 7B = 0 Set up second equation:
A - B = 16 Multiply by 5:
5A - 5B = 80 Subtract the first equation from this equation:
5A - 7B = 0 5A-5A leaves nothing. -5B - (-7B) = 2B To subtract, reverse the sign and add.:
2B = 80 Solve:
B = 40 Substitute 40 for B in first equation:
A - 40 = 16 Solve:
A = 56 The two numbers are 56 and 40. To check divide by 8. 56/8 = 7 and 40/8 = 5. So the ratio between the numbers is 7/5 and difference is 16 CHECK!
Or you can use 1 equation to get to the answer:
7x-5x=16 solve
2x=16
x=8 substitute 8 into the equation:
7 times 8 is 56. 5 times 8 is 40
56–40 is 16 The two numbers are 56 and 40.
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Step-by-step explanation:
given the ratio
7:5 then if I multiply a then its 7a:5a=7:5(same)
now ATQ
7a-5a=18
now solve the equation
