We have to find the years in which private expenditure was at least double the public expenditure. Since the public-private line graph is given in percentage. We have to see if the line for private expenditure is at least twice the % line for public expenditure. Only for 1975 and 1976 this is the case.
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Can someone add the solution to the above problem ?

The answer is C and the explanation is above.

Ask if you do need further assistance
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How? year 1975 the difference between the two in percent is 46% ( private was about 72% & public was about 26%). in year 1976, i see 40% difference ( private 70% & public about 30%)
Can someone explain to me? Thank you.

For how many of the years shown was the amount of private health expenditures at least double the amount of public health expenditures?


Double means two times this value or more

Now, you double a value NOT making the difference but calculate the increase in term of %

So, if you have 20 and want the 50% you need to make : 20 \times 1.50 = 30

Now from the graph



The first value is around 28 * 2.0 = 56 but the value of private is 72 so is more than double

The second is 30 * 2.0 = 60 and the value is 70 so it fits

The others do not , they going to shrink

The answer is c
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