Question

A/b=2/5,b/c=5/7 Найдите отношение а/с

Answer 1

$\frac{a}{b} \times \frac{b}{c} = \frac{2}{5} \times \frac{5}{7} \\ \frac{a}{c} = \frac{2}{7}$

Answer 2

To find the ratio of a/c, we can first find the individual values of a, b, and c, and then calculate a/c. Let's solve the equations step by step.

Given: A/B = 2/5 and B/C = 5/7

Step 1: Find the value of B To find the value of B, we can set the two ratios equal to each other and solve for B:

A/B = B/C 2/5 = B/C

Cross-multiply: 2C = 5B

Now, solve for B: B = 2C/5

Step 2: Find the value of A We know A/B = 2/5, and we just found the value of B as B = 2C/5. Now, we can substitute B in terms of C to find A:

A = (2/5) * B A = (2/5) * (2C/5) A = 4C/25

Step 3: Find the value of C We know B/C = 5/7. We already found the expression for B in terms of C, so we can substitute it in the equation to solve for C:

B/C = 5/7 (2C/5) / C = 5/7

Now, cross-multiply and solve for C: 7 * 2C = 5 * 5C 14C = 25C

Subtract 14C from both sides: 25C - 14C = 0 11C = 0

C = 0

Step 4: Find the value of A/C Now that we know C = 0, we can find the value of A/C:

A/C = (4C/25) / C A/C = (4 * 0 / 25) / 0 A/C = 0/0

When dividing by zero, the result is undefined.

Therefore, the ratio A/C is undefined in this case.